Beta carotene may reduce risk of heart attack

Elderly people may be able to reduce their risk of heart attack by eating fruit and vegetables rich in beta carotene, according to Dutch researchers.

As part of the Rotterdam study, the researchers followed the dietary and medical histories of 4802 people aged from 55 to 95 for four years. During this period 124 of the participants had heart attacks.

Analysis of the results showed that those with the highest daily intakes of beta carotene had a 45 per cent lower risk of heart attack, compared to people consuming the lowest amount of beta carotene. A combination of beta carotene from food and supplements led to a 50 per cent reduction in risk.

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Vitamin A linked to learning and memory

Results of a study published in the journal Neuron suggest that vitamin A affects cells in a region of the brain linked to learning and memory.

Researchers created special genetically altered mice, known as knockout mice, which were missing two brain-specific receptors for the vitamin. Although the mice developed normally, compared to ordinary mice they performed poorly on standard intelligence tests.

On further examination, the brain cells of the knockout mice were seen to lack the ability to undergo necessary changes in order to facilitate learning.

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Calcium reduces heart disease risk

Results from the Iowa Women's Health Study suggest that calcium products reduce the risk of death due to ischemic heart disease.

The study involved 34 486 postmenopausal Iowa women 55 to 69 years old and without a history of ischemic heart disease who completed a dietary questionnaire in 1986. Through 1994, there were 387 deaths due to ischemic heart disease.

Analysis of the results showed that women with a high intake of calcium had a 30 to 35 per cent reduction in risk of death due to the disease. Women who took a daily calcium supplement with a dose between 1 and 500 mg had a 44 per cent reduced risk of death. Women whose dietary intake of calcium was high but who did not take supplements had a 46 per cent reduced risk. Intake of milk products did not appear to affect risk.

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High beta carotene intake lowers breast cancer risk

The results of a Swedish study add further weight to the evidence that diets high in Beta Carotene can reduce breast cancer risk.

Of the 644 women who took part in the study, 273 had been diagnosed with breast cancer. The women were asked to recall details about their diets at various times in their lives.

The results showed that women whose diets had included beta carotene for 20 years or more had a lower risk of breast cancer than women whose diets included beta carotene in more recent years.

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High vitamin E levels can prevent age-related decline in brain function

Older people with higher vitamin E levels are less likely to experience the decline in intellectual function that occurs with aging.

Austrian researchers assessed vitamin E levels and intellectual function in almost 1800 adults aged from 50 to 75. They found that those with higher vitamin E levels were less likely to have low scores on tests of intellectual capacity. These tests are used to measure decline in Alzheimer’s Disease and other types of dementia.

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What is Fibromyalgia?

Fibromyalgia syndrome is a common form of generalized muscular pain and fatigue. The name "fibromyalgia" means pain in the muscles and the fibrous connective tissues (the ligaments and tendons). This condition is referred to as a "syndrome" because it's a set of signs and symptoms that occur together. (A sign is what the physician finds on examination; a symptom is what a person reports to the doctor.) Fibromyalgia is especially confusing and often misunderstood because almost all it symptoms are also common in other conditions. In addition, it does not have a known cause.

The name "fibromyalgia" has largely replaced the term "fibrositis," which was once used to describe this disorder. The "itis" means "inflammation" - a body process that can result in pain, swelling, warmth, redness, and stiffness. Early reports of this condition described inflammation in muscles. However, during the past 50 years investigators have proven that inflammation is not a significant part of fibromyalgia.

Fibromyalgia is a form of "soft-tissue" or muscular rheumatism rather than "arthritis of a joint." The word "rheumatism" refers to pain and stiffness associated with arthritis and related disorders of the joints, muscles, and bones. Fibromyalgia mainly affects muscles and their attachments to bones. Therefore, although fibromyalgia may feel like a joint disease, it is not a true form of arthritis and does not cause deformities of the joints.

Unfortunately, because certain syndromes lack physical and laboratory findings (signs), but depend mostly on a person's report of complaints and feelings (symptoms), these syndromes are often viewed as not being real or important. In the past, fibromyalgia suffered from this type of negative thinking.

Over the past ten years, however, fibromyalgia has been better defined through studies that have established guides for its diagnosis. These studies have shown that certain complaints, such as generalized muscular pain and tender points, are present in people with fibromyalgia and not commonly present in healthy people or people with other rheumatic conditions. These diagnostic features separate fibromyalgia from other types of conditions that have chronic muscle and bone pain.

Symptoms and Signs

Pain

Pain is the most prominent symptom of fibromyalgia. It is generally felt all over, although it may start in one region, such as the neck and shoulders, and seems to spread over a period of time. Fibromyalgia pain has been described in a variety of ways including: burning, radiating, gnawing, sore, stiff, and aching. It often varies according to time of the day, activity level, weather, sleep patterns, and stress. Most people with fibromyalgia say that some degree of pain is always present. They sense that the pain is mainly in their muscles and often note that fibromyalgia feels like a persistent flu. For some people with fibromyalgia the pain may be quite severe.
Although the general physical examination is usually normal, and individuals may look well, careful examination of their muscles will demonstrate very tender areas at specific locations. The presence and pattern of theses characteristic "tender points" separate fibromyalgia from other conditions. Not all physicians are familiar with the evaluation of these tender points. However, most rheumatologists (specialists in arthritis and rheumatism) do know when and how to perform such an examination.
The tender areas in fibromyalgia are similar in location to sore and tender areas in other common muscle and bone pain disorders such as tennis elbow and trochanteric bursitis (inflammation of the outer side of the hip). They are found in many locations and are almost always on both sides of the body. People often are not aware of the exact location or even the presence of many of these tender points until they are specifically examined by a doctor.

Fatigue and Sleep Disturbances

About 90 percent of people with fibromyalgia describe moderate or severe fatigue with lack of energy, decreased exercise endurance, or the kind of exhaustion felt with the flu or with lack of sleep. Often the fatigue is more of a problem and more troubling than the pain. Generally, people with fibromyalgia wake up feeling tired, even after sleeping throughout the night. They may be aware that their sleep has become lighter and that they wake up during the night. Scientific studies have demonstrated that most people with fibromyalgia have an abnormal sleep pattern, especially an interruption in their deep sleep.
The fatigue in fibromyalgia is similar to the in another condition called chronic fatigue syndrome (CFS). Some people with fibromyalgia have symptoms of CFS, and vice versa. for example, many people with CFS have the tender points and symptoms considered to be diagnostic of fibromyalgia. Because there is an overlap in these two common syndromes, it may not be possible to separate these two conditions, and one doctor may give a diagnosis of fibromyalgia whereas another may call the condition chronic fatigue syndrome.

Nervous Systems Symptoms

Changes in mood and thinking are common in fibromyalgia. Many individuals feel "blue" or "down," although only about 25 percent are truly depressed. Some people also feel very anxious. Generally, the depression and anxiety seem to follow the onset of fibromyalgia symptoms and may be the result of the fibromyalgia rather than a cause of it. However, some researchers feel there may be a "biologic link" between fibromyalgia and some forms of depression and chronic anxiety.
As with other chronic illnesses, people with fibromyalgia may report difficulty concentrating or performing simple mental tasks. There is no evidence that these problems become more serious. Similar problems have been noted in many people with sleep disturbances of all kinds or with mood changes.
People with fibromyalgia may have feeling of numbness and tingling in their hands, arms, feet, legs, or sometimes in their face. These feeling can suggest other disorders such as carpal tunnel syndrome, neuritis, or even multiple sclerosis. Therefore, people with fibromyalgia often undergo numerous tests for such conditions, only to find that the test results are normal.

Other Problems

Headaches, especially muscular (tension) and migraine headaches, are common in fibromyalgia. Abdominal pain, bloating, and alternating constipation and diarrhea are also common. This may resemble irritable bowel syndrome or "spastic colon." Similar bladder spasms and irritability may cause urinary urgency or frequency. The skin and circulation are often sensitive to temperature and moisture changes, resulting in temporary changes in skin color.

How is Fibromyalgia Diagnosed?

Fibromyalgia is diagnosed by the presence of widespread pain in combination with tenderness at most of the specific locations. Unfortunately, no one laboratory test or x-ray can diagnose fibromyalgia. Such tests are only helpful when they prove the presence of other conditions, such as low thyroid hormone, (hypothyroidism), which can cause fibromyalgia signs and symptoms. A careful history and physical examination can identify other conditions that may cause chronic pain and fatigue and identify the "tender point" that are seen in fibromyalgia.

Because the complaints of fibromyalgia are so general and often bring to mind other medical disorders, many people undergo complicated and often repeated evaluations before they are diagnosed as having fibromyalgia. Furthermore, since not all doctors have been trained to recognize this disorder, it is important for people to see a rheumatologist or other doctor who is very familiar with the diagnosis and treatment of this condition.

What Causes or Triggers Fibromyalgia?

The single exact cause of fibromyalgia is unknown. Many different factors, alone or in combination, may trigger this disorder. For example, a number of stresses - such as an illness, physical trauma, emotional trauma, or hormonal changes - may precipitate the generalized pain, fatigue, sleep, and mood problems that characterize fibromyalgia. Physical or emotional trauma could precipitate fibromyalgia in a number of ways. For example, a physical trauma such as having an infection or flu could lead to certain hormonal or chemical changes that promote pain and worsen sleep. In addition, people with fibromyalgia may become inactive, depressed, and anxious about their health, further aggravating the disorder.

In recent years, studies have shown that in fibromyalgia the muscle is especially vulnerable to decreased circulation and minor injury. Therefore, smoking and inappropriate exercise or poor posture may aggravate fibromyalgia. Research has also looked at the role of certain hormones or body chemicals that may alter pain, sleep, and mood. Eventually, this research should result in a better understanding of fibromyalgia, as well as more effective treatment, and even prevention!

How is Fibromyalgia Treated?

Currently, treatments for fibromyalgia include:

  • Medications that diminish pain and improve sleep
  • Nutraceuticals and other alternative therapies that relieve symptoms
  • exercise programs that involve muscle stretching and improve cardiovascular fitness
  • relaxation techniques and other measures to help you relax tense muscles
  • educational programs to help you cope with fibromyalgia.

As with most chronic illnesses, the treatment should be tailored to meet your individual needs. Some people with fibromyalgia have mild symptoms and need very little treatment once they understand what fibromyalgia is and what worsens their condition. Most people do benefit from a comprehensive care program.

Medications

The anti-inflammatory medications used to treat arthritis and many rheumatic conditions do not have a major effect in fibromyalgia. However, modest doses of aspirin, ibuprofen, or acetaminophen may help to provide some pain relief and lessen stiffness. Narcotic pain relievers, tranquilizers, and cortisone derivatives have been shown to be ineffective and should be avoided because of their potential side effects.

Medications that promote deeper sleep and also relax muscles help many people with fibromyalgia. These include amitriptyline (Elavil), doxepin (Sinequan), cyclobenzaprine (Flexeril), and related medications. Although these medications are also used to treat depression, in people with fibromyalgia they are generally used in very low doses and only at bedtime. Thus, they are not specifically used as antidepressants or tranquilizers in the treatment of fibromyalgia but may relieve pain and improve sleep.

Although many people sleep better and have less discomfort when they take these medications, the improvement varies greatly from person to person. In addition, the medications may have side effects such as daytime drowsiness, constipation, dry mouth, and increased appetite. These side effects are rarely severe, but can be disturbing and may limit the use of these drugs. Therefore, a number of different medicines may need to be tried and doses adjusted in consultation with a doctor.

Exercise and Physical Therapy

Two principles of treating fibromyalgia are to increase cardiovascular (aerobic) fitness and to stretch and mobilize tight, sore muscles. You may be reluctant to exercise if you are already in pain and feel tired. Low or non-impact aerobic exercises such as brisk walking, biking, swimming, or water aerobics are generally the best way to start such a program. Exercise on a regular basis, such as every other day, and gradually increase to reach a better level of fitness. Gently stretch your muscles and move your joints through an adequate range of motion daily and before and after aerobic exercise. Physical therapy may be helpful and could include techniques such as: heat, ice, massage, whirlpool, ultrasound, and electrical stimulation to help control pain. Physical therapists may also be consulted to design a specific exercise program to improve posture, flexibility, and fitness.

Coping with Fibromyalgia

Often people with fibromyalgia have undergone many tests and have seen many different specialists while in search of an answer. This leads to fear and frustration, which may increase the pain. People with fibromyalgia are often told that since they look well and their tests are normal, they are not suffering from a real disorder. Their family and friends, as well as physicians, may doubt the reality of their complaints, increasing their feelings of isolation, guilt, and anger.

You and your family should understand that fibromyalgia is a real cause of chronic pain and fatigue and must be dealt with as with any chronic illness. Yet, fibromyalgia is not life-threatening and causes no deformity. Although symptoms may vary, the overall condition rarely worsens over time.

Often just knowing fibromyalgia is not a progressive, crippling disease allows people to stop additional expensive testing and to develop a more positive attitude toward their condition. Relaxation techniques, such as meditation, visual imagery, progressive muscle relaxation, yoga, or biofeedback may also be helpful. You should examine your own sleep patterns and avoid aggravating factors such as excess caffeine and alcohol. If you feel depressed or very anxious, it is important to get help from a mental health professional. The more you learn about your condition, and the more you take an active role in finding the best means to lessen your symptoms, the better the outcome.

Support groups and educational classes organized by the Arthritis Foundation have been a source of help for many people with fibromyalgia. Just knowing that you are not alone can be a source of support.

Some people with fibromyalgia have such severe symptoms that they are unable to function well at work or socially. These individuals may require greater attention in a program that employs physical or occupational therapists, medical social workers, rheumatology nurses, mental health professionals, rehabilitation counselors, and sleep specialists.

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WHAT ARE VITAMINS?

Vitamins are substances which, in small amounts, are necessary to sustain life. They must be obtained from food as they are either not made in the body at all, or are not made in sufficient quantities for growth, vitality and well-being. A deficiency of a particular vitamin causes disease symptoms which can only be cured by that vitamin.

Vitamins are chemically unrelated substances and all are organic. Organic substances are those that contain carbon and come from materials that are living, such as plants and animals, or that were once living, for example petroleum or coal.

It is impossible to sustain life without all the essential vitamins.

What Vitamins Do

Vitamins have many functions and influence the health of nearly every organ in the body. Their combination with other substances such as minerals, proteins and enzymes brings about certain chemical reactions. Individual vitamins have specific functions which vary widely and can overlap. They are involved in growth, the ability to produce healthy offspring and the maintenance of health. They play a role in metabolism, enabling the body to use other essential nutrients such as carbohydrates, fats, proteins and minerals. Vitamins are important for a normal appetite, in digestion, mental alertness and resistance to bacterial infections.

In addition to satisfying the body’s daily needs and preventing deficiency diseases, vitamins have several therapeutic effects. For example, niacin can be used to lower cholesterol and vitamin A derivatives can be used to treat acne. Large doses of vitamins may slow, or even reverse many diseases previously thought an inevitable part of aging, such as cancer, heart disease, osteoporosis, impaired immunity, nerve degeneration and other chronic health problems.

In the USA the following are officially listed as vitamins:

Vitamin A

Vitamin C

Vitamin D

Vitamin E

Vitamin K

The B vitamin complex containing:

Vitamin B1 (thiamin)

Vitamin B2 (riboflavin)

Vitamin B3 (niacin)

Vitamin B6 (pyridoxine)

Vitamin B12 (cobalamin)

Pantothenic acid

Biotin

Folic acid

There are other substances whose vitamin status has not been established. Some researchers consider these to be vitamins but this is not generally accepted. Such substances include choline, inositol, para-aminobenzoic acid (PABA) and coenzyme Q10.

Vitamins are usually divided into two categories: fat soluble and water soluble.

Vitamins A, D, E and K are fat soluble. They require an adequate supply of minerals and fats to be absorbed in the digestive system and are stored in the liver. The remaining vitamins are water soluble with any excess being excreted in the urine. These need to be replenished frequently.

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WEIGHT LOSS

Despite the availability of low fat foods and increasing awareness of the risks, obesity is still on the increase. However, despite the prevalence of obesity, many people do not consume enough essential nutrients to keep themselves healthy, and overweight and poor nutrition are major risk factors for some of the most common diseases in our society. These include high cholesterol levels, atherosclerosis, hypertension, heart disease, diabetes, some types of cancer, gallstones, gout, stroke, gallbladder disease, liver disease, infertility and arthritis. People who are overweight often meet with disapproval in their daily lives and may suffer psychological and social difficulties.

Hand in hand with the increase in obesity has come a national obsession with weight loss. Many overweight people are drawn to fad diets that promise fast results with minimal effort, only to see the weight go back on just as quickly once they return to their regular diet. Such a pattern of repeated weight loss and gain may contribute to lifelong obesity. The only way to lose weight and keep it off is to develop, and stick to a healthy, nutrient-dense, balanced diet and a regular exercise program.

Obesity

Many people think of obesity as an excess of total body weight whereas in fact, it is excess body weight as fat. Being overweight may also be defined in terms of how someone feels about him or herself, and psychological factors play an important role in obesity and weight loss. Many people, particularly young women, think they are overweight when they may actually be underweight. For many people the optimum weight may not be as low as they would like.

An ideal or optimum weight is difficult to define. A commonly used way to assess body weight is the body mass index (usually abbreviated as BMI). A person's BMI is calculated by dividing their weight in kilograms by the square of their height in meters. A BMI within the range 20 to 25 is considered normal. A value of between 25 and 30 is considered overweight and a value over 30 is defined as obese.

Factors Contributing to Obesity

Obesity is an enormously complex problem and there are various theories as to the cause. It is likely that there are several factors contributing to the weight problem of a particular person. For years the prevailing scientific view was that in order for weight loss to occur, energy (or calories) in needed to be less than the energy (or calories) out. This usually means either eating less or exercising more, and the best results seem to happen when someone does both. However, new research suggests that weight management is more complicated than this and other factors contributing to obesity mean that a calorie is not the same for everyone. Some people seem to have higher metabolic rates and burn up food more efficiently than others. This may be due to a combination of genetic and psychological factors, gender, hormonal imbalances, poor liver function, food allergies and in some cases, medication use.

A Healthy Weight Loss Diet

While different diets suit different people, there are some general guidelines that can help people to make better food choices on a weight loss diet. A daily diet built around high levels of complex carbohydrates, low fat levels and moderate protein intake is the best approach for those wishing to lose weight. It is also important to obtain vitamins and minerals in amounts at least as high as the RDAs. A diet that consists of a wide variety of wholesome, minimally processed foods, fortified foods and, in some cases, supplements will play a part in safe, effective weight loss.

Calories

The energy value of food is measured in kilocalories, which is usually shortened to calories. The word 'calorie' comes from the Latin for 'heat' and a calorie is defined as the amount of heat needed to raise the temperature of one gram of water by 33.8 degrees Fahrenheit. The metric measurement is kilojoules. One calorie is equivalent to 4.2 kilojoules (kJ).

Food is usually defined in terms of calories as a way of comparing the relative energy value it holds. Fat, carbohydrate and protein are known as macronutrients because they provide energy. Vitamins and minerals are known as micronutrients as they have no energy value.

1 gram of fat provides 9 calories (38 kJ)

1 gram of protein provides 4 calories (17 kJ)

1 gram of carbohydrate provides 4 calories (17 kJ)

Fat

Fat is the most concentrated food source of calories and many weight loss diets are based around limiting fat. Many people trying to lose weight aim to exclude fat from their diets altogether in the belief that this will bring faster results. However, while excessive intakes of certain fats can contribute to obesity and health problems, it is important to remember that some types of fats are essential nutrients and are necessary for health.

Carbohydrate

Carbohydrate foods vary in the rate at which they are absorbed into the bloodstream. Foods high in simple sugars such as glucose and sucrose (table sugar) are quickly absorbed and this leads to a sharp rise in insulin production to move the sugar out of the blood. This is followed by a sharp drop in blood glucose and a craving for more sweet food. This contributes to obesity as these foods are high in calories. Complex carbohydrates are absorbed more slowly into the blood than simple carbohydrates, which leads to a slower insulin response. In this way, blood sugar levels tend to be more consistent, avoiding the sharp rises and falls of a diet high in simple sugars. Sucrose also seems to cause a greater increase in blood fat levels than more complex carbohydrates.

In fat tissue, insulin facilitates the storage of glucose and its conversion to fatty acids, and also slows the breakdown of fatty acids. Sharp rises in insulin may contribute to obesity and it seems that blood insulin levels correspond to body fat stores. The longer and more often insulin levels are high, the more likely sugars are to be converted to and stored as fat. Eating large amounts of foods high in both fat and sugar increases weight gain even more.

Eating too many sugar-rich foods such as cookies, cakes and candy that contain refined carbohydrates increases the risk of nutritional deficiencies as there may not be enough room for nutrient-dense foods. Sugars and refined carbohydrates require vitamins and minerals for metabolism but unlike whole grains, they do not contain enough of these vital nutrients.

Exercise

No weight loss program is complete without an exercise component. When a dieter concentrates solely on food restriction to achieve results there is a loss of both body fat and muscle. This is less than ideal as muscle helps burn fat. The most effective weight loss programs involve both diet and exercise.

Aerobic exercise is the best way to lose fat. It burns extra calories, a few hundred or more per hour of exercise, depending on the type of exercise, a person's weight and how hard they exercise. Over time, exercise builds muscle which raises metabolic rate and improves the ability to burn calories and reduce fat tissue. Exercise has the added advantage of increasing metabolic rate for up to 24 hours after exercise has been completed.

More complete exercise programs also include anaerobic exercise as this is the kind which builds strength and flexibility. Strength training can also help with weight loss and improve body image and self-esteem. Building muscle mass will also increase metabolic rate, which burns more. The best fitness programs involve a balance between aerobic fitness and flexibility and strength training.

Vitamin and Minerals

Vitamin and mineral supplements can be helpful during and after weight loss as many people on weight loss diets do not consume adequate amounts of vitamins and minerals. Some common sources of nutrients such as calcium and vitamin E are found in high quantities in high calorie foods which people on weight loss diets tend to avoid.

B Vitamins

B vitamins are essential for the metabolism of food and optimal intake is necessary to ensure that this takes place effectively. Biotin and pantothenic acid supplements have been used in weight loss programs.

Minerals

Extra minerals may also be useful in preventing deficiency, especially in people whose fiber intakes are high, as fiber reduces absorption of calcium, iron, zinc, copper, manganese, and molybdenum.

Antioxidants

Since weight loss usually involves a mild process of detoxification, with the body burning fat and sometimes other tissues, antioxidants may be useful. These include beta carotene, vitamin C, vitamin E and selenium.

Chromium

Limited research suggests that moderate increases in chromium, in the form of chromium picolinate, may cause weight loss, reduce fat and increase muscle mass. Because of these reports, chromium picolinate supplements have become very popular.

Researchers involved in a 1997 study assessed the effects of chromium yeast and chromium picolinate on lean body mass in 36 obese patients during and after weight reduction with a very low calorie diet. During the 26-week treatment period, subjects received either placebo or 200 mcg chromium yeast or 200 mcg chromium picolinate in a double-blind manner. After 26 weeks, chromium picolinate-supplemented patients showed increased lean body mass whereas the other treatment groups still had reduced lean body mass.1

In a 1997 study done at the University of Texas at Austin, researchers examined the effects of 400 mcg of chromium and exercise training on young, obese women. The results showed that exercise training combined with chromium nicotinate supplementation resulted in significant weight loss and lowered the insulin response to an oral glucose load.2

Essential Fatty Acids

Essential fatty acid supplements may also be useful in improving fatty acid metabolism. This is particularly important if the diet is very low in fat. Cold-pressed flaxseed oil is high in both omega-3 and omega-6 fatty acids, and is a good way to obtain these oils. Usually, three or four teaspoons a day are adequate. As cofactors that help in fatty acid metabolism, zinc, magnesium, vitamins A, C, niacin, pyridoxine, biotin, choline and carnitine may also be useful.

Other Nutrients

Other nutrients and supplements that have been used to help in weight loss include coenzyme Q10, acetyl-L-carntitine, spirulina and chitosan.

Herbs

Herbs that have been used to aid in weight loss include brindleberry (Garcinia cambogia), chickweed (Stellaria media), bladderwrack (Fucus vesiculosus) and plantain (Plantago ovata).

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VEGETARIANS

Vegetarian diets have increased greatly in popularity in the last 20 years, with a growing number of studies linking eating meat to a greater risk of heart disease and other degenerative disorders. A balanced vegetarian diet supplies all the vitamins and minerals the body requires and is usually higher in fiber and lower in fat, cholesterol, protein and sugar than the typical Western diet.

Vegetarian Diet and Disease

Many medical studies have shown that a low fat vegetarian diet can lessen the risks of developing cardiovascular disease, diabetes, osteoporosis, kidney stones and other common diseases. Vegetarians usually have lower cholesterol and blood pressure than people who eat meat. Low fat, high fiber diets that include a variety of fruits, vegetables, whole grains and beans also help to prevent cancer.

The results of a 17-year study involving 11,000 vegetarians were published in the British Medical Journal in 1996. Researchers investigated the links between dietary habits and disease in vegetarians and health conscious people. The results showed that overall, the mortality rate in this group was around half that of the general population, and that daily consumption of fresh fruit was associated with a lower risk of death from any disease.1

The Vegetarian Diet

Vegetarians choose their diets for reasons of culture, belief or health. There is no single vegetarian eating pattern, and diets differ in the extent to which they avoid animal products. Vegans completely exclude meat, fish, poultry, eggs and dairy products. Lacto-vegetarians avoid meat, fish, poultry and eggs. Lacto-ovo vegetarians avoid meat, fish and poultry.

The more restricted the diet, the more care must be taken to ensure that all nutrient needs are met. A vegetarian diet does exclude rich sources of several nutrients such as iron, zinc and vitamin B12, and it is important to include plenty of alternative plant sources of the vitamins and minerals commonly found in meat, fish and eggs. Milk is a good source of calcium and riboflavin, and may supply as much as half the daily needs. Other sources, such as dark green leafy vegetables, must be eaten in quite large quantities in order to meet these needs.

A balanced diet for a lacto-ovo vegetarian might include all of the following foods in a day:

l two to three servings of low fat milk or milk products.

l three to four servings of protein-rich cooked dried beans and peas, seeds or nuts.

l at least five servings of fruits and vegetables.

l at least six servings of whole grain breads and cereals.

Protein

Proteins are made up of 20 main naturally-occurring amino acids and some other minor ones. Some of these amino acids are essential constituents of the diet as they cannot be made in the body, whereas others are nonessential. Meat, fish, eggs, milk and soybeans contain all the essential amino acids and are known as complete proteins. Grains, beans, peas, nuts and seeds contain some amino acids and not others, and are called incomplete proteins. Two incomplete protein foods, eaten together, can provide a complete protein, for example, baked beans on toast or lentils and rice.

A varied vegetarian diet provides adequate amounts of amino acids and usually meets or exceeds requirements for dietary protein. A typical Western diet is probably too high in protein, and vegetarians often eat less protein than meat eaters. This may partly explain their reduced risk of many degenerative diseases as high protein intakes promote excretion of essential minerals.

Fats

Vegetarians often have a higher intake of omega-6 polyunsaturated fats from nuts, seeds and vegetable oils. A high intake of these fats has been linked to an increased risk of cancer, particularly when the omega-6 to omega-3 fatty acid ratio becomes too high. Those who avoid fish may not get adequate amounts of omega-3 oils in their diets and should make sure to include plant sources of omega- 3 oils such as flaxseed oil in the diet. Population studies have shown that, compared to vegetarians, those who eat fish tend to have lower blood pressures and lower blood fat levels.2

Vegetarians and Vitamins

Riboflavin

Riboflavin may be low in vegan diets as the main sources are milk and milk products. Other sources include fortified breakfast cereals, yeast extract and mushrooms. Someone who eats no milk or meat can meet the RDA for riboflavin by including all of the following in a daily diet: three slices of whole meal bread, a cup of almonds, half an avocado and average servings of spinach, broccoli and mushrooms.

Vitamin B12

Animal foods are the only reliable sources of vitamin B12. Vegetarians who eat dairy products generally obtain adequate vitamin B12 from these sources. Vegans tend to have lower vitamin B12 intakes which may not reach recommended levels, and should make sure they include vitamin B12-fortified foods or supplements in their diets. This is particularly important for women who are, or who plan to become, pregnant.

Sea vegetables and fermented soybean products such as miso also contain forms of vitamin B12, although some research suggests that the human body may not be able to absorb these forms and they may even block true vitamin B12 absorption.3 Many vegetarian and vegan products are fortified with vitamin B12, including yeast extract, vegetable stock and soya milk. In developing countries, food may contain bacteria and other micro-organisms which are a source of vitamin B12. In Western countries better hygiene and food processing removes these sources of vitamin B12.

Vitamin D

Vitamin D is present in vegetarian diets in dairy products. Vegans tend to have low vitamin D intakes, fortified margarine being the major dietary source. In most countries, sufficient vitamin D can be obtained through manufacture in the skin in response to sunlight. Vegans who do not get enough exposure to sunlight may be advised to take a vitamin D supplement; although pregnant women should not take large amounts as there is an increased risk of fetal deformities.

Vitamin E

Vitamin E needs increase in those whose diets are higher in polyunsaturated fats from nuts, seeds and vegetable oils. As vegetarians often have a higher intake of such fats, they need to make sure their vitamin E intake is adequate to protect against harmful free radical damage to these fats.

Vegetarians and Minerals

Refining removes most of the vitamin and mineral content from grains. For example, flour refining causes a 77 per cent loss in zinc; rice refining causes a loss of 83 per cent; and processing cereals from whole grains causes an 80 per cent loss. It is particularly important for vegetarians who avoid animal sources of minerals like zinc and iron to ensure their intake of whole grains is adequate.

Iron

Both vegetarians and nonvegetarians often have difficulty in meeting RDA for iron, but this is particularly the case in premenopausal vegetarian women. Iron is present in animal foods in organic 'heme' form and in plant foods in inorganic 'nonheme' form. The heme and nonheme forms of iron are absorbed by different mechanisms.4 About 20 to 30 per cent of heme iron is absorbed, compared with only around 2 to 5 per cent of nonheme iron. Vitamin C consumed in the same meal as nonheme iron improves absorption by up to 50 per cent as it helps to convert dietary iron to a soluble form and also helps counteract the reduction in absorption that occurs in the presence of phytates. Vitamin A and beta carotene can also improve nonheme iron absorption.5 Tea reduces the absorbability of iron and should be drunk between meals rather than with them.

A premenopausal woman can meet the RDA for iron by including all the following in a daily diet: ten dried apricots; three slices of whole wheat bread; one cup of lentils; and one cup each of cooked spinach, broccoli and green beans.

Iron levels in the body are controlled by absorption. When intakes in the diet are lowered, absorption ability can improve. Some research suggests that this gradually happens in vegetarians. In cases of iron deficiency absorption efficiency increases from around 5 to 10 per cent to about 10 to 20 per cent.

Zinc

Some vegetarians have lower than recommended zinc intakes as they avoid meat and seafood, which are good sources. Phytates also reduce zinc absorption. Vegetarians need to make sure that they include enough zinc-rich pulses, seeds and whole grains in their diets.

The RDA for zinc can be obtained by including all of the following in a daily diet: three slices of wholemeal bread, one cup of cooked chickpeas, a handful of pumpkin seeds, a serving of muesli, two tablespoons of wheatgerm, half a cup of almonds, a serving of peas and one ounce of peanut butter.

Calcium

Although vegans do not eat dairy products - which are the main sources of calcium - with careful planning, it is possible to get enough calcium from plant foods. Vegans may need slightly less calcium than meat eaters as they appear to have better absorption and lower excretion. However, studies of women who have followed vegan diets for long periods indicate that they may be at higher risk of osteoporosis and may benefit from calcium supplements.6

Leafy green vegetables, seaweed and tofu made with calcium sulfate are good vegetarian sources of calcium. The amount of calcium in tofu varies from brand to brand, and it is worth comparing quantities between different brands.

The RDA for calcium can be obtained by including all of the following in the daily diet: four ounces of firm tofu processed with calcium sulfate, a cup of cooked spinach, two oranges, a cup of broccoli, four slices of whole wheat bread and a cup of almonds. It can be difficult for vegan children to get enough calcium in their diets as they have to eat relatively large quantities of bulky food.

Iodine

Milk and milk products are important sources of iodine so vegans must be careful to include other iodine-rich foods in their diets. These include seaweed, cereals and vegetables grown in iodine-rich soil.

Vegetarians and Supplements

Vegetarians who are not always able to follow a varied, balanced diet may benefit from supplements. Women who are, or who hope to become, pregnant or who are breastfeeding may be advised to take vitamin B, calcium, iron and zinc supplements.

Iron supplements can be useful for premenopausal vegetarian women who often find it difficult to get enough iron. Zinc supplements are also useful and if taken for long periods, it is also advisable to take a copper supplement of around 2 mg per day.

Vegetarian Teenagers

Vegetarian diets can be safe for teenagers; although this presents special challenges as teenagers need sufficient calories, protein, vitamins and minerals for rapid growth. Again the key is to eat a variety of foods; including fresh fruit and vegetables, whole grain products, nuts, seeds, beans and peas, and preferably dairy products and eggs.

Vegetarian Children

A vegetarian diet can provide the nutrients needed for a child's growth and development. Research into vegetarian children has shown that they are similar to meat eaters in height, weight and skinfold measurement.7 They are also less likely to be obese. Vegan children tend to be lighter and leaner and may be shorter. Nutritional deficiencies are generally no more common in vegetarian children than among those who do eat meat, although in some cases iron levels may be lower.8

Children who eat vegetarian diets often eat fewer convenience foods and dairy products, and more starchy foods such as pulses, fruit and vegetables. Vegetarian girls may start menstruation at a slightly later age which may be protective against breast and other hormone-dependent cancers later in life. Vegetarian diets in children may be beneficial in protecting against disorders such as bowel problems, obesity, cardiovascular disease and cancer by establishing healthy dietary patterns which may be carried on into adult life.

Vegan diets are not usually recommended for children under 18 years of age due to sporadic eating habits and the relatively large volumes of food needed to meet the recommended intakes for nutrients such as calcium, iron and zinc.

Children Under Five

A diet that is healthy for an adult may not be appropriate for a very young child and high fiber, low fat diets may not be sufficiently high in certain nutrients. Young children need energy and nutrient-dense foods such as cereals, vegetable oils, bananas and avocados. Large intakes of high fiber or watery foods typically found in vegetarian and vegan diets may not be advisable in very young children.

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OSTEOPOROSIS

Osteoporosis, which literally means "porous bones", is the result of a long-term decline in bone mass which, in severe cases, causes the bones to break under the weight of the body. Particularly badly affected bones include the spinal vertebrae, the thigh bone and the radius (shorter arm bone). Over 25 million Americans may be affected by osteoporosis and 80 per cent of those are women. Although the problem also occurs in men, postmenopausal women are particularly susceptible, with around 35 per cent of women suffering from osteoporosis after menopause.

Symptoms of Osteoporosis

The symptoms of osteoporosis are often absent until fractures occur, although in some cases there may be a loss of height, a hunched back or back pain. Osteoporotic fractures affect 50 per cent of women and 30 per cent of men over 50. These fractures are particularly serious as demineralized bones shatter when they break and usually take longer to heal. Radiological examination can be used to measure bone mineral density and assess the risk of fracture.

Causes of Osteoporosis

Around 35 per cent of women suffer from osteoporosis after menopause and, although it is less common, the problem occurs in a similar way in men. Osteoporosis is more common in Caucasians and Asians because they are often smaller boned.

Most of the bone loss seen in osteoporosis in women occurs in the first five to six years after menopause due to a decline in circulating female hormones and an age-related reduction in vitamin D production. Genetic factors seem to play a part in osteoporosis but behavioral and hormonal factors may be more important. Sufficient body fat and muscle are necessary to keep hormone levels high enough to maintain bone mineral content. Athletes and premenopausal women whose menstrual periods have stopped may also be at increased risk of osteoporosis due to alterations in their hormone levels.

Adequate intakes of calcium, vitamin D, magnesium and boron are also necessary. Diets high in dairy products, protein, sugar, alcohol, salt, caffeine-containing drinks and very high in fiber also seem to increase the risk of the disorder, most likely due to effects on mineral absorption and metabolism. People on weight-reducing diets are also at risk as they avoid foods high in bone-building nutrients.

Inactivity leads to an increased risk of osteoporosis, as does gastric surgery and certain types of medications such as corticosteroids.

Treatment of Osteoporosis

The conventional treatment for osteoporosis is estrogen therapy but this is not suitable for some women due to the increased risk of breast cancer. Some women are treated with calcitonin, a hormone that inhibits removal and promotes formation of bone. It is available in injection forms and as a nasal spray. Intake of calcium and vitamin D must also be adequate. Newer osteoporosis drugs include alendronate, which inhibits bone breakdown; and raloxifene, a selective estrogen receptor modifier.

Osteoporosis Prevention

Exercise

Regular exercise plays a vital part in preventing loss of bone mass. Weight-bearing exercises such as walking, jogging and yoga contribute to increases in bone density and prevention of bone loss. Exercise also helps build muscle mass which can help protect bones from injury. It also improves strength and flexibility, decreasing susceptibility to falls.

Diet

A healthy diet can reduce the incidence of osteoporosis by ensuring the development of a favorable peak bone mass during the first 30 to 40 years of life. Adequate nutrient intake early in life is vital for bones to reach their maximum density so that they are strong enough to support the body even when they lose mass later in life. However, it is never too late to slow the bone loss seen in osteoporosis, and early postmenopausal years are an important time to ensure optimal intake of nutrients including calcium, magnesium, boron and vitamin D.

Recent research suggests that including soybeans in the diets of postmenopausal women may decrease the risk of osteoporosis. Soybeans contain compounds called phytoestrogens which act in a similar way to estrogen and have beneficial effects on bone mineral density.

Caffeine-containing drinks can increase the loss of calcium in the urine. Diet soda drinks which contain phosphoric acid can alter the calcium phosphorus balance and contribute to calcium loss from the bones. Consuming large amounts of these drinks can increase the risk of osteoporosis. Nicotine and alcohol also adversely affect bone mineral density. High salt intakes seem to increase calcium excretion, lowering bone mineral density and increasing the risk of osteoporosis. In a study published in 1995, Australian researchers investigated the influence of urinary sodium excretion on bone density in a 2 year study of 124 postmenopausal women. The results showed that increased sodium excretion was linked to decreases in bone density.1

While dairy products are good sources of calcium, there is concern that their protein content can actually increase the loss of calcium from bone. Researchers involved in the Nurses Health Study analyzed the diets of over 77,000 participants in the study and looked at the rates of bone fractures. Results showed that women who drank two or more glasses of milk per day had around a 45 per cent increased risk of hip fracture and a 5 per cent increased risk of forearm fracture compared to women who drank one glass or less per week. There was also no drop in risk with intake of calcium from other dairy foods.2 A varied diet which includes nondairy sources of calcium is likely to be more beneficial in protecting against osteoporosis.

Vitamins, Minerals and Osteoporosis

B Vitamins

B vitamin deficiencies may contribute to osteoporosis, particularly those of folate, vitamin B12 and vitamin B6. This may be partly due to the effects of increased homocysteine levels on bone metabolism.

Vitamin D

Vitamin D regulates the absorption and use of calcium and phosphorus, which are vital for normal growth and development of bones. Vitamin D is necessary for calcium absorption and increases the deposition of calcium into bones. In cases of vitamin D deficiency, the body increases production of parathyroid hormone which removes calcium from the bones and leads to bone thinning.

Research suggests that there may be a genetic link between vitamin D receptor types and osteoporosis. It is also possible that patients with osteoporosis have impaired conversion of vitamin D to its most active form. The ability to produce vitamin D in the skin may decline with age and bone loss may increase in the winter months when people have less exposure to sunshine. People with a certain type of vitamin D receptor may be more susceptible to osteoporosis, and research suggests that women with different types of vitamin D receptors respond differently to vitamin D supplements.3

A study done in 1997 at Tufts University in Boston showed reduced rates of bone loss and fractures in men and women over 65 who took calcium and vitamin D supplements. Researchers assessed the effects of calcium (500 mg per day) and vitamin D (700 IU per day) on 176 men and 213 women aged 65 years or older. After a three-year period, those taking the supplements had higher bone density at all body sites measured. The fracture rate was also reduced by 50 per cent in those taking the supplements.4

Vitamin D supplements may also be useful in preventing bone loss in patients taking corticosteroid drugs. In a study published in 1996, researchers at the University of Virginia found that calcium and vitamin D supplements helped prevent the loss of bone mineral density in those taking the drugs for arthritis, asthma and other chronic diseases.5 Vitamin D supplements may also be useful in reducing the risk of osteoporosis due to long-term use of anticonvulsant drugs.

However, other studies have not shown any reduction in fracture rates in those taking vitamin D supplements. A 1996 study which was carried out in Amsterdam looked at the effects of either vitamin D or a placebo on 2500 healthy men and women over the age of 70 who were living independently. The participants received a placebo or a daily dose of 400 IU of vitamin D for a three-and-a-half year period. Dietary calcium intake was the same in both groups. Forty-eight fractures were observed in the placebo group and 58 in the vitamin D group.6

Vitamin K

Low levels of vitamin K have been seen in sufferers of osteoporosis. In a Japanese study published in 1997, researchers investigated the relationship between bone mineral density, vitamin K levels and other biological parameters of bone metabolism in 71 postmenopausal women and 24 women with menopausal symptoms receiving hormone replacement therapy. The results showed that women with reduced bone mineral density had lower levels of vitamin K1 and K2 than those with normal bone mineral density.7 Low levels have also been seen in osteoporotic men.8

Boron

Boron acts with calcium, magnesium and phosphorus in the metabolism of bone. Deficiency seems to affect calcium and magnesium metabolism and affects the composition, structure and strength of bone, leading to changes similar to those seen in osteoporosis.9 Combined boron and magnesium deficiency seems to worsen osteoporosis, suppress bone building and cause decreased magnesium concentrations in bone.10 Supplements of around 3 mg per day have been shown to enhance the effects of estrogen in postmenopausal women. This is likely to contribute to its beneficial effects on bone health.11 Studies done in 1994 in athletic college women suggest that boron supplements decrease blood phosphorus concentration and increase magnesium concentration. Both of these changes are beneficial to bone building.12

Calcium

Osteoporosis is not merely a loss of calcium from bone, although calcium deficiency does contribute to osteoporosis. The National Osteoporosis Foundation estimates that the average adult in the US gets only 500 to 700 mg per day. The US government has recently raised its recommendation for daily calcium intake. For men and women aged from 19 to 50, the RDA is now 1000 mg, and for those over 50 it is 1200 mg.

The new RDA for adolescents is 1300 mg and adequate calcium intake during this time of life plays a vital part in allowing bones to reach their maximum density so that they are strong enough to support the body even when they lose density later in life. Studies suggest that calcium intake in adolescence is often below the recommended levels. Researchers involved in a 1994 USDA study measured calcium intake in 51 girls aged 5 to16 years old. They found calcium intake to be below the recommended dietary allowance for 21 out of 25 girls aged 11 or over. These studies suggest that the current calcium intake of American girls during puberty is not enough to enable bones to develop maximum strength, and that increased intakes may be necessary.13 A 1993 study published in the Journal of the American Medical Association suggests that calcium supplements may be beneficial in adolescent girls. Researchers gave daily calcium doses of 500 mg or placebo to 94 girls and then measured bone mineral density and bone mineral content at the lumbar spine. The results showed that increasing calcium intake led to significant gains in bone mass.14

However, it is never too late to slow the bone loss seen in osteoporosis, and early postmenopausal years are also an important time to ensure optimal intake. A 1997 study done at King's College Hospital in London suggests that high calcium intakes are linked to bone mineral density in elderly women. Researchers assessed calcium intake in 124 women aged from 52 to 62 and also measured bone mineral density at the spine, hip and the os calcis bone in the foot. Results showed that women with high calcium intakes had higher bone mineral density.15 Results from the Rotterdam Study, which involved 1856 men and 2452 women aged 55 years and over, show that high calcium intakes also protect against bone loss in men.16

Taking calcium supplements later in life can slow the bone loss associated with osteoporosis, and treatment which combines calcium and estrogen is likely to be better at building bone than treatment with estrogen alone. In a 1998 study, researchers analyzed the results of 31 studies and found that the postmenopausal women who took estrogen alone had an average increase in spinal bone mass of 1.3 per cent per year, while those who took estrogen and calcium supplements had an average increase of 3.3 per cent. Increases in bone mass in the forearm and upper thigh were also greater in women taking supplements. The added benefit from the calcium was seen when the women increased their intake from an average of 563 mg per day to 1200 mg per day.17

It is recommended that postmenopausal women who are not on estrogen therapy consume 1500 mg calcium per day. Multivitamin supplements often do not provide enough calcium and separate supplements may be necessary. Supplements should be taken in divided doses throughout the day, with a maximum of 500 mg being taken at any one time.

Fluoride

Bones seem to be more stable and resistant to degeneration when the diet is adequate in fluoride. Sodium fluoride supplements have been used to treat osteoporosis.3 Researchers involved in a 1998 study published in the Annals of Internal Medicine compared the vertebral fracture rates in 200 women over a four-year period. One group was given 20 mg of fluoride and 1000 mg of calcium daily, and the other group received only calcium. The rate of new fractures in the fluoride group was 2.4 per cent compared to 10 per cent in the calcium only group.18 Sustained release of fluoride in doses of 23 mg per day appears to be more beneficial than forms which are quickly absorbed from the gut.19 However, a 1996 study done in Argentina suggests that the increases in bone mineral density are not maintained after sodium fluoride therapy is stopped.20

The treatment of osteoporosis with fluoride supplements is controversial as there is the possibility that fluoride bone is not always stronger than normal bone. There may be an increase in the number of hairline fractures in the hips, knees, feet and ankles. In 1983/1984, a study of bone mass and fractures was begun in 827 women aged 20-80 years in three rural Iowa communities selected for the fluoride and calcium content of their community water supplies. Residence in the higher-fluoride community was associated with a significantly lower radial bone mass in premenopausal and postmenopausal women, an increased rate of radial bone mass loss in premenopausal women, and significantly more fractures among postmenopausal women.21 Fluoride therapy may increase the requirement for calcium as more is needed for bone formation.

Magnesium

Magnesium and calcium interact in many body functions including that of bone formation. Women with osteoporosis may have lower magnesium levels than women without the disorder. In a 1995 study, results showed that women whose dietary intakes were less than 187 mg per day had a lower bone mineral density than women whose average intakes were more than 187 mg.22

Magnesium is essential for the normal function of the parathyroid glands, metabolism of vitamin D, and adequate sensitivity of bone to parathyroid hormone and vitamin D. Magnesium deficiency may impair vitamin D metabolism which adversely affects bone building.23 Magnesium deficiency is also known to cause resistance to parathyroid hormone action which affects calcium balance and may cause abnormal bone formation.24 However, magnesium excess inhibits parathyroid hormone secretion which means that bone metabolism is impaired under positive as well as under negative magnesium balance.25 Maintaining normal calcium-to-magnesium balance is very important in the prevention of osteoporosis.

Supplements may help to increase bone mineral density in postmenopausal women, thus reducing the risk of osteoporosis. In a 1990 study, US researchers investigated the effect of a dietary program emphasizing magnesium instead of calcium for the management of postmenopausal osteoporosis. Nineteen women on hormone replacement therapy (HRT) received 500 mg magnesium and 600 mg calcium, and seven other women on HRT did not receive supplements. The results showed that in one year, those women given the supplements had greater increases in bone mineral density than those who were not. Fifteen of the 19 women had had bone mineral density below the spine fracture threshold before treatment; within one year, only seven of them still had values below that threshold.26

In a 1993 study, Israeli researchers assessed the effects of supplemental magnesium in 31 postmenopausal women who received six 125 mg tablets daily for six months and two tablets for another 18 months in a two-year trial. Twenty-three symptom-free postmenopausal women were assessed as controls. The results showed that 22 patients responded with a 1 to 8 per cent rise of bone density. The mean bone density of all treated patients increased significantly after one year and remained unchanged after two years. In control patients, the mean bone density decreased significantly.27

Zinc

Zinc accompanies calcium in the mineralization of bone, and is lost when calcium is lost from bone. Recent research in monkeys suggests that diets low in zinc during adolescence may increase the risk of osteoporosis later in life, as bones may not develop properly.

In a 1996 study, researchers studied zinc deficiency in two groups of ten monkeys. Both groups were given nutritionally balanced diets but one group received 50 mg of zinc per gram of food while the other group only received 2 mg of zinc per gram of food. Eight of the monkeys were then studied throughout their lives to ages equivalent to that of ages 10 to 16 in human girls. The researchers found that the monkeys on low zinc diets had slower skeletal growth, maturation and less bone mass than the other monkeys, with substantial differences noticed in the lumbar spine. The differences were only apparent during rapid growth phases in the monkeys, especially during pregnancy.28

Other Minerals

Chromium may help to boost the bone-building effects of insulin and may have a role in the maintenance of bone density and prevention of osteoporosis.29 Copper is necessary for bone formation, and inadequate intake can cause the loss of calcium from bones, reduced bone formation and deformities. Manganese deficiency may also increase loss of calcium from the bone. Silicon may have a role in the prevention and treatment of osteoporosis, and supplements are used to increase bone mineral density.

Herbal Medicine and Osteoporosis

Herbs used to treat osteoporosis include horsetail (Equisetum arvense), oat straw (Avena sativa), alfalfa (Medicago sativa) and hawthorn (Crataegus oxyacantha). Herbs commonly used to alleviate the side effects of menopause include black cohosh (Cimicifuga racemosa) and dong quai (Angelica sinensis).

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OLDER PEOPLE

By the year 2010, one in five people in the developed world will be aged 65 or over and the needs of an aging population will have a huge impact on society in the next century. Increasing research effort is being directed into ways of helping older people stay healthy, independent and mobile. Lifestyle and environmental factors play a part in some of the most common age-related illnesses including heart disease, osteoporosis, cancer, high blood pressure and chronic infection; which means that people have at least partial control over how well they age. Good nutrition early in life affects longevity and quality of life in later years. Aging changes occur at different rates in different people and it is unclear exactly how these are related to diet and other lifestyle factors. However, there is plenty of scientific evidence to show that good eating habits throughout life can help to promote physical and mental well-being in older people.

Diet and Aging

The dietary needs of people in their fifties or sixties are different from those who are younger. For most vitamins and minerals, needs are higher; although for some nutrients they actually fall. The needs of people in their seventies and eighties are different again. Mainstream nutrition is beginning to recognize these differences and some of the new RDAs take into account the needs of those who are older.

Energy intakes and energy expenditure vary widely among elderly people, and are very different in those who are healthy, sick or institutionalized. Older people tend to consume fewer calories than younger people, probably due to loss of muscle, reduced activity levels and lower metabolic rates. As total food intake decreases, individual nutrient intakes also decrease, making it more important to eat nutrient-dense foods and leaving less room for sweets and other empty calorie foods.

Deficiencies of many nutrients are common in elderly people. Normal changes associated with aging, some medications for chronic disease, and relatively common disorders such as diabetes, high blood pressure, constipation and diarrhea can result in higher requirements for some nutrients. Many social and physiological factors such as loneliness, limited income, reduced interest in food, decreased sense of smell and taste, difficulty in chewing or swallowing and reduced vision may also lead to changes in an older person's diet.

New research findings are being published all the time but relatively little is known about how the aging process affects the ability of the body to digest, absorb and retain nutrients. The diets of elderly people are often deficient in several nutrients including vitamins A, C, D, E, B12, thiamin, riboflavin, pyridoxine, niacin, folic acid, calcium, iron, magnesium and zinc. These deficiencies may be due to lower dietary intake, decreased absorption, altered metabolism or increased excretion. They often develop slowly and may mimic the normal changes of aging. Elderly people are particularly at risk of marginal vitamin and mineral deficiencies and early recognition of malnutrition is very important in preventing diseases, maintaining a healthy immune system and increasing lifespan.

Digestion

As many as 30 per cent of people aged over 65 develop the inability to produce stomach acid which can lead to reduced absorption of certain vitamins and minerals; including folic acid, calcium, iron and vitamin B12. By the age of 80, as many as 40 per cent of people may be unable to produce stomach acid. Improving digestion can be valuable in improving health in elderly people.

Immunity

Aging is generally associated with a decline of the immune response, which may be linked to a cumulative marginal deficiency of trace minerals and vitamins. Vitamin and mineral deficiencies, particularly of zinc, selenium, and vitamin B6, all of which are prevalent in aged populations, adversely affect immune responses. Because aging and malnutrition exert cumulative influences on immune responses, many elderly people have poor cell-mediated immune responses and are therefore at a high risk of infection. Supplementation with high doses of single nutrients may be useful for improving immune responses of self-sufficient elderly people living at home. Treating nutritional deficiencies in elderly people can reduce the risk of infections and possibly slow the aging process.1

Vitamins, Minerals and Older People

Vitamin A

Many older people may consume less than recommended levels of vitamin A, which may lead to poor vision, dry skin, lowered immunity, and may contribute to diseases such as cancer. However, large doses of pre-formed vitamin A could be harmful for elderly people as these may be cleared from the blood and tissues more slowly than in younger people. Vitamin A in the form of beta carotene may be more beneficial.

Creams that contain the vitamin A-derivative, tretinoin, may help to combat premature skin aging. In a 1997 study researchers investigated the activity of enzymes known as metalloproteinases which break down collagen, and found that exposure to ultraviolet light increased the activity of these enzymes. This may lead to premature skin aging. The researchers then found that tretinoin could block the enzyme activity, opening up the possibility that tretinoin may be useful in treating patients with signs of premature skin aging.2

B Vitamins

Low dietary intake of B vitamins is quite common in elderly people and may lead to reduced mental functioning, skin and hair problems, suppressed immunity, depression and other emotional disorders, general weakness, and gastrointestinal problems. Improved nutrition often reverses the symptoms of deficiency, although in some cases permanent damage may occur.

Thiamin

Thiamin deficiency may be relatively common in older people and supplements are likely to be useful in improving quality of life. In a 1997 study, New Zealand researchers measured red blood cell concentrations of a thiamin-dependent enzyme in 222 people aged over 65 years. This measurement was done twice in three months. Thirty-five people who had low levels at both measurement times were divided into two groups. Half were given either a thiamin supplement of 10 mg per day and half were given a placebo for three months. The researchers then assessed blood pressure, body weight, height, body mass index, hand grip strength and cognitive function in the subjects. The results showed that the supplements decreased blood pressure and weight. Those taking the supplements reported improved quality of life, sleep and energy levels.3

Vitamin B6

Vitamin B6 requirements increase considerably in elderly people, possibly due to reduced absorption. Low vitamin B6 levels may also lead to increased risk of several disorders, including heart disease. In a study published in 1996 Dutch researchers studied the vitamin B6 intake and blood levels in 546 elderly Europeans, aged from 74 to 76, with no known vitamin B6 supplement use. They also examined links with other dietary and lifestyle factors, including indicators of physical health. The results showed that 27 per cent of the men and 42 per cent of the women had dietary vitamin B6 intakes below the mean minimum requirements. Twenty-two per cent of both men and women had low blood levels.4 The neurological and immunological effects of deficiency are usually reversible with supplementation.

Folate

Many elderly people do not consume enough folate in their diets. In a 1996 Canadian study, researchers investigated folate and vitamin B12 intakes and body levels in 28 men and 30 women aged over 65 years. The results showed that 57 per cent of men and 67 per cent of women were at risk of deficiency.5 One of the most common disorders in elderly people is cardiovascular disease. There is increasing evidence that folic acid deficiency plays a role in the development of this disease through an increase in homocysteine levels. Supplements may be useful for their protective effects.

Folate deficiency may also cause or worsen the mental difficulties often experienced by older people. In a study done in 1996 in Spain, researchers analyzed the relationship between mental and functional capacities and folate status in a group of 177 elderly people. In this study, almost 50 per cent of the people had folate intakes below recommended values. Those with poor test results had significantly lower folate levels.6

Vitamin B12

Inadequate vitamin B12 intake is relatively common in elderly people, with 10 to 20 per cent of elderly people having some level of vitamin B12 deficiency. This can result in reduced mental capacity and other neurological disorders that can resemble Alzheimer's disease. Older people often have a reduced capacity to absorb vitamin B12 due to low stomach acid and lack of intrinsic factor, the compound necessary for absorption. A stomach disorder known as atrophic gastritis may also limit absorption. Some experts believe that the incidence of pernicious anemia resulting from low vitamin B12 levels may be more common than previously thought, with up to 800,000 elderly people in the US suffering from the disease.

Low vitamin B12 levels in older people may also reduce the effectiveness of the immune response. Recent research has shown that elderly people with low vitamin B12 levels may have impaired antibody responses to vaccination even though their immune systems are apparently functioning adequately.7

Supplementation can prevent irreversible neurological damage if started early. Elderly people with vitamin B12 deficiency may show psychiatric or metabolic deficiency symptoms even before anemia is diagnosed. Screening for low vitamin B12 levels is necessary in elderly people with mental impairment, although it has also been found that deficiency states can still exist even when blood levels are higher than the traditional lower reference limit for vitamin B12. Patients who are most at risk of vitamin B12 deficiency include those with gastrointestinal disorders, autoimmune disorders, Type I diabetes mellitus and thyroid disorders, and those receiving long-term therapy with gastric acid inhibitors.8

Other B Vitamins

Mild riboflavin deficiency may be quite common in elderly people whose diets are low in red meat and dairy products. Niacin deficiency is also relatively common.

Vitamin D

Vitamin D absorption from food may decrease with age. Elderly people often also get less exposure to the sun and have a reduced capacity for skin synthesis, a major source of vitamin D. This may increase the risk or worsen the symptoms of osteoporosis, cancer, diabetes and arthritis.

Studies show that elderly people, particularly those who are housebound or in institutions, may be at high risk of vitamin D deficiency. Older people who frequently use sunscreens may also be more likely to suffer from vitamin D deficiency. A study published in 1998 in the New England Journal of Medicine found vitamin D deficiency in 57 per cent of a group of 290 patients who were admitted to hospital. In a subgroup of the patients who had no known risk factors for vitamin D deficiency, the researchers found that 42 per cent were deficient. They concluded that vitamin D deficiency was probably a substantial problem.9

In recognition of the increased vitamin D needs of older people, the RDAs have been raised. For adults under 50, the RDA is 200 IU; while for those over 50, it is now 400 IU; and for those over 70, it is 600 IU.

Osteoarthrtitis

Osteoarthritis sufferers who have low vitamin D intakes seem to suffer more severe symptoms than those whose intakes are high. In a study done in 1996, researchers at Boston University studied more than 500 elderly people with osteoarthritis of the knee. They found that those with the lowest intakes and blood levels of vitamin D were three times more likely to see their disease progress than people with high intakes and blood levels. Vitamin D may help reduce the cartilage damage seen in osteoarthritis.10

Osteoporosis

Vitamin D deficiency increases the risk of osteoporosis in elderly men and women and supplements may be useful in reducing bone loss and the occurrence of fractures. In a study published in 1997, researchers at Tufts University in Boston assessed the effects of calcium (500 mg per day) and vitamin D (700 IU per day) in 176 men and 213 women aged 65 years or older. When bone density was measured after a three-year period, those taking the supplements had higher bone density at all body sites measured. The fracture rate was also reduced by 50 per cent in those taking the supplements.11 However, other studies have not shown any reduction in fracture rates in those taking vitamin D supplements.12 Vitamin D supplements may also be useful in preventing bone loss in patients taking corticosteroid drugs.13

Antioxidants

Research suggests that the antioxidants beta carotene, vitamin C, vitamin E and selenium may help to prevent aging-related diseases such as cardiovascular disease, cancer, cataracts, rheumatoid arthritis and Alzheimer's disease.

Growing evidence suggests that free radical damage may be an underlying cause of the aging process, thus leaving open the possibility that antioxidants may be able to slow this process.

Beta Carotene

As well as exerting protective effects against various aging-related diseases, beta carotene may protect against memory impairment and other loss of mental function in older people. In a recent Dutch study, researchers studied 5182 people aged 55 to 95 from 1990 to 1993. They found that those with intakes of less than 0.9 milligrams of beta carotene per day were almost twice as likely to have impaired memory, disorientation and problem solving difficulty as those with intakes of 2.1 milligrams of beta carotene.14

Researchers involved in a 1997 Swiss study found similar results. The study, which was reported in the Journal of the American Geriatrics Society, involved 442 men and women, aged from 65 to 94 in 1993. Antioxidant levels were originally tested in 1971 and then again in 1993, when the participants were also given memory-related tests. Higher vitamin C and beta carotene levels were associated with higher scores on free recall, recognition and vocabulary tests.15

Vitamin C

Vitamin C deficiency in elderly people can increase susceptibility to many disorders. Low vitamin C levels are associated with lowered immunity, which increases the risk of infection. In a study published in 1997, French researchers assessed vitamin C levels in 18 elderly patients in hospital. The patients were divided into three groups: those with acute infection, those who were malnourished, and a control group. Those with acute infection had considerably lower vitamin C levels than those in the other groups.16

Low vitamin C intakes also increase the risk of cardiovascular disease in elderly people. During a study which was begun in 1981, USDA researchers assessed the health and nutrition status of 747 elderly people aged 60 years and over. Particular attention was paid to the foods the participants usually ate and the levels in their blood of the antioxidant vitamins C, E and beta carotene. The researchers following up the subjects from nine to 12 years later found that among people who ate lots of dark green and orange vegetables, there were fewer deaths from heart disease and other causes. The results showed that a daily intake of more than 400 mg and higher blood levels of vitamin C were linked to reduced risk of death from heart disease.17

Vitamin E

High vitamin E intakes are linked to lower risks of several disorders including cardiovascular disease, cancer, Parkinson's disease and cataract. Supplements have also shown beneficial effects in several studies.

A study by researchers from the National Institute on Aging, published in 1996, examined the effects of vitamin E and vitamin C supplement on mortality risk in 11 178 persons aged from 67 to 105 who were taking part in the Established Populations for Epidemiologic Studies of the Elderly from 1984 through 1993. During the follow-up period, there were 3490 deaths. The results showed that those using the vitamin E supplements had a 34 per cent lower risk of death when compared to those not using vitamin E supplements, and around half the risk of death from coronary disease. Those taking both vitamin C and vitamin E had a 42 per cent reduced risk.18

Vitamin E supplements also improve the effectiveness of the immune system in elderly people. In a 1997 study of 88 healthy people aged 65 or older, those who took 200 mg (300 IU) each day for about four months showed an improvement in immune response. Researchers assessed the effects of either 60 mg (90 IU), 200 mg (300 IU) or 800 mg (1333) on a measure of immune system strength known as delayed hypersensitivity skin response. The results showed that those who took 200 mg a day had a 65 per cent increase in immune function. Those taking 60 mg or 800 mg of vitamin E also showed some improvements in immune function but the ideal response was seen in those taking 200 mg.19 Vitamin E may also provide relief from some of the symptoms of menopause, particularly hot flashes.20

Many studies suggest that vitamin E supplements are beneficial for elderly people, as it can be difficult to get high levels of vitamin E in the diet. Most studies use doses that range from 536 mg (800 IU) or even 804 mg (1200 IU). Such doses far exceed the RDAs, and it is not possible to get such large amounts of vitamin E from food without consuming a high fat diet.

Calcium

High calcium intakes are associated with reduced risk of some types of cancer and high blood pressure. Optimal calcium intake is particularly important in preventing the bone-thinning associated with osteoporosis. Although the problem also occurs in men, women are at particularly high risk of osteoporosis, with as many as 35 per cent of women suffering from the disease after menopause. Most of the bone loss seen in osteoporosis in postmenopausal women occurs in the first five to six years after menopause due to low calcium intake, a decline in female hormones, and an age-related reduction in vitamin D production.

It is never too late to slow the bone loss seen in osteoporosis and early postmenopausal years are an important time to ensure optimal calcium intake. Some research shows that taking calcium supplements later in life may lower vertebral fracture rate and prevent bone density decrease in elderly people.

Treatment which combines calcium and estrogen is likely to be better at building bone than treatment with estrogen alone. In a 1998 review, researchers analyzed the results of 31 studies and found that the postmenopausal women who took estrogen alone had an average increase in spinal bone mass of 1.3 per cent per year, while those who took estrogen and calcium supplements had an average increase of 3.3 per cent. Increases in bone mass in the forearm and upper thigh were also greater in women taking supplements. The added benefit from the calcium was seen when the women increased their intake from an average of 563 mg per day to 1200 mg per day.21

Iron

Iron deficiency is common in elderly people as they often have reduced stomach acid and therefore reduced absorption ability. Low blood plasma levels of iron can contribute to fatigue, heart disease and deterioration in mental functioning.

Iron requirements are lower in women who have reached menopause as they no longer lose iron in menstrual blood. However, deficiency is still relatively common and all elderly people should ensure they get sufficient iron in their diets. A 1997 National Institute of Aging study suggests that low iron levels are linked to an increased likelihood of death in elderly people. Researchers looked at the iron status of nearly 4000 men and women aged 71 and over. Results showed that low iron levels increased the risk of total and coronary heart disease deaths. Those with higher iron levels had decreased risk. Men with the highest iron levels had only 20 per cent of the risk of dying of heart disease of those with the lowest levels. Women with the highest levels were about half as likely to die of heart disease compared to those with the lowest levels.22

The iron overload disorder, hemochromatosis, can result in increased risk of heart disease, liver problems and other disorders. This is one of the most common inherited diseases in certain groups of people, and middle-aged and older men may be particularly badly affected. Iron supplements should be avoided in these cases.

Magnesium

Marginal magnesium deficiency is considered to be very common, especially in the elderly. Inadequate intake may contribute to cardiovascular disease, high blood pressure, osteoporosis, diabetes and various other disorders. Supplements are likely to be beneficial in older people.

Selenium

Selenium is a vital part of the antioxidant enzyme, glutathione peroxidase, and so may protect against free radical damage and its consequences. It is also necessary for thyroid and immune system function, which may be disrupted in older people. Optimal intake may also help combat psychological disorders like depression, anxiety, fatigue and appetite loss.

Sodium

Sodium restriction may be a useful way to lower blood pressure in elderly people suffering from hypertension. In a two-month double-blind, randomized, placebo- controlled crossover study published in 1997 in The Lancet, researchers found that modest reduction in salt in the diets of elderly people led to lower blood pressure. The study involved 29 patients with high blood pressure and 18 with normal blood pressure. The average blood pressure fall was 8.2/3.9 mmHg in the normal subjects and 6.6/2.7 mmHg in those with high blood pressure.23 In those with normal blood pressure, cutting salt may have little effect, according to an analysis of 83 studies published in the Journal of the American Medical Association in 1998.24

Zinc

Inadequate consumption of zinc-rich foods can result in reduced sense of taste and possibly lead to reduced appetite or increased consumption of sugary or salty foods that may aggravate malnutrition. Zinc is vital for wound-healing and an effective immune response, and a deficiency can leave elderly people susceptible to infection and prolong recovery from illness. Elderly people often have zinc-poor diets and low blood levels.

Menopause

Menopause is when a woman's menstrual periods stop altogether and a woman is said to have gone through menopause when her menstrual periods have stopped for an entire year. This usually occurs between the ages of 45 and 55, although it can happen as early as 35 or as late as 65 years of age. It can also result from the surgical removal of both ovaries. The physical and emotional signs and symptoms that go with menopause usually last around one to two years or more, and vary from woman to woman. The changes are a result of hormonal changes such as estrogen decline, the aging process itself, and stress.

The physical signs and symptoms associated with menopause may include hot flushes, heart palpitations, irregular periods, vaginal dryness, loss of bladder tone, headaches, dizziness, skin and hair changes, loss of muscle strength and tone, and decreased bone mineral density. Emotional changes associated with menopause may include irritability, mood changes, lack of concentration, difficulty with memory, tension, anxiety, depression and insomnia.

Hormone replacement therapy (HRT) is often used to reduce many of the symptoms of menopause. It also offers significant protection against osteoporosis and heart disease. However, it may increase the risk of certain types of cancer and some women are unable or unwilling to use HRT.

Regular exercise and stress reduction techniques can be helpful in reducing the symptoms of menopause. Dietary measures that may be beneficial include limiting or avoiding drinks that contain caffeine or alcohol, spicy foods, and heavy meals. Soy foods such as tofu, which contain compounds known as phytoestrogens, have been shown to reduce menopausal symptoms in many women. A woman's risk of disorders such as heart disease and osteoporosis increases after menopause, and the various dietary measures and supplements outlined above can be used to prevent these.

Herbal Medicines and Older People

There are many herbs that can be beneficial for older people. These include tonics such as ginseng (Panax ginseng and Eleutherococcus senticosus), which can improve vitality and resistance to disease; ginkgo (Ginkgo biloba), which can improve mental function; damiana (Turnera diffusa), which can boost libido; ginger (Zingiber officinale), which can improve circulation; and hawthorn (Crataegus oxyacantha), which is a heart tonic. Herbs which may be useful during menopause include chaste tree (Vitex agnus castus), St John's wort (Hypericum perforatum), motherwort (Leonurus cardiaca), dong quai (Angelica sinensis), and black cohosh (Cimicifuga racemosa).

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