Conventional and alternative practitioners alike acknowledge the importance of a healthful diet. Alternative practitioners, however, place more emphasis on dietary intervention in some conditions where conditional medicine would turn first to drugs or even surgery. Treatment of atherosclerosis, for example, may take the form of an extremely low-fat diet with a program of meditation, exercise, and support-group therapy.

What we eat is influenced by many factors, including personal preference, lifestyle, culture, religion, and ethical and moral attitudes. But what we eat can also have a therapeutic effect. The most common reason for a change in diet is to lose weight, but many people also alter their diet to prevent or treat diseases such as cancer, or heart disease, the main cause of diet-related premature death.

DIETARY THERAPY
Diet as therapy has been practiced for centuries. The father of medicine, Hippocrates, wrote extensively about the therapeutic use of diet, yet until relatively recently modern medicine has largely forgotten the overwhelming role of diet, except as related to problems such as obesity and diabetes. With the growth of nutritional science in the 20th century, specific foods have been recognized as risk factors in disease. For example, too much fat, and saturated animal fat in particular, is now widely recognized as a risk factor of heart disease and some cancers. Equally, too much refined food and too little fiber causes a range of digestive and bowel disorders, from constipation to irritable bowel syndrome - and may even be a cause of some cancers. Too much salt may exacerbate high blood pressure and reactions to food-trigger allergies.

BASIC NUTRITION
Carbohydrates, proteins, and fats - macronutrients or "energy nutrients" - provide fuel in the form of calories. Carbohydrates, the body's main energy source, are divided into two types: simple carbohydrates are sugars, such as cane sugar and molasses; complex carbohydrates include starches, such as those found in potatoes and whole grains.

Proteins support tissue growth and repair, and help produce antibodies, hormones, and enzymes, which are essential for all the body's chemical reactions. Protein sources include meat, fish, dairy products, poultry, dried beans, nuts, and eggs.

Dietary fat protects internal organs, provides energy, insulates against cold, and helps the body absorb certain vitamins. There are three kinds of fats: saturated, found in meat, dairy products, and coconut oil; monosaturated, in canola, olive, and peanut oils; and polyunsaturated, in corn, cottonseed, safflower, sesames, soybean, and sunflower oils.

Your diet also supplies the important micronutrients we call vitamins and minerals. They are needed only in trace amounts, but the absence or deficiency of just one can cause major illness. With a few exceptions, the body does not manufacture micronutrients and so must obtain them from food. Thirteen vitamins and some twenty minerals are considered essential for health.

DIET PLANNING

• Eat a variety of foods. This will help ensure that you get the calories, protein, fiber, vitamins, minerals, and other nutrients you need.

• Control your weight. Keep within recommended weight limits for your age, sex, and build.

• Eat a low-fat, low-cholesterol diet. Ideally, no more than 30 percent of your daily calories should come from fat, and no more than 10 percent should come from saturated fat.

• Eat plenty of vegetables, fruits, and grains. More than half of your daily calories should come from carbohydrates, rich in nutrients and low in fats; 80 percent of those calories should be from complex carbohydrates.

• Eat sugar and salt in moderation. Sugar is high in calories and promotes tooth decay. Too much salt may increase the risk of developing high blood pressure. Prepared foods are notoriously high in salt or other forms of sodium, so check labels.

• If you drink alcohol, do so in moderation. Alcohol provides calories but no nutrients, and too much is harmful. However, some studies indicate that moderate consumption of red wine may actually lower the risk of heart disease. "Moderation" generally means one drink a day for women or two drinks for men.

NUTRITIONAL SUPPLEMENTS
If you consistently eat a well-balanced diet of fresh fruits, vegetables, grains, and some animal protein, you probably don't require a nutritional supplement. Multi-nutrient supplements offer insurance for those times when eating well is a challenge - and can be indispensable during pregnancy or when you are ill, injured, or under great mental or physical strain.

Generally, vitamins and minerals are commended for daily use as a preventive measure. Supplements do, however, figure in the dietary recommendations of many therapies. Orthomolecular medicine, a form of nutrient therapy, uses combinations of vitamins, minerals, and amino acids normally found in the body to treat specific conditions such as asthma, heart disease, depression, and schizophrenia. Such therapy can also be used to maintain general good health.

Taking vitamins or minerals in excess can upset the natural balance of nutrients. The fat-soluble vitamins - A, D, E, and K - can be retained in your body and may be toxic in high amounts. The rest are water-soluble and are unlikely to be toxic; excess amounts are excreted in the urine. Always take supplements in moderation; they are safe in doses at or below RDAs, but higher doses may be harmful and should be taken only under the guidance of a doctor or a registered dietitian.

Supplement doses are measured by weight in milligrams (mg), or thousandths of a gram; in micrograms (mcg), or millionths of a gram; or in a universal standard known as international units (IU).

FOOD ALLERGIES AND SENSITIVITIES
Some people cannot tolerate certain foods or food additives; the most common culprits include dairy products, soybeans, peanuts, wheat, eggs, and shellfish. Allergic reactions can be very severe, even causing death, whereas sensitivities can cause troublesome symptoms such as rashes or bloating. Food intolerance may even be a factor in hyperactivity and many chronic diseases such as rheumatoid arthritis.

An elimination diet can help you pin down what food or foods are causing the reaction, and banning the offenders from your diet is one way to deal with this problem. A controversial method called desensitizing aims to train the body to accept foods it would otherwise not tolerate. One fairly common intolerance, that for milk sugar, can be addressed by adding a specific enzyme to the diet or by limiting the intake of dairy products to those, such as yogurt, that are more easily digested.

FOOD GUIDE PYRAMID

• 1. Fats, Oils, & Sweets Group - Use sparingly. One teaspoon of butter, oil, or margarine is a single serving.
• 2. Milk, Yogurt, & Cheese Group - 2-3 servings. One serving equals 1 cup of milk or yogurt, 1 ½ oz. of natural cheese, or 2 oz. of processed cheese.
• 3. Meat, Poultry, Fish, Dried Beans, Eggs, & Nuts Group - 2-3 servings. One serving is 2 to 3 oz. of cooked lean meat, poultry, or fish. An ounce of meat equals one egg or ½ cup cooked dried beans.
• 4. Vegetable Group - 3-5 servings. One serving equals 1 cup of raw leafy greens, ½ cup of other vegetables, or ¾ cup of vegetable juice.
• 5. Fruit Group - 2-4 servings. One serving from the fruit group is equal to one apple, orange, or banana; ½ cup of chopped, cooked, or canned fruit; or ¾ cup of fruit juice.
• 6. Bread, Cereal, Rice, & Pasta Group - 6-11 servings. One serving equals one slice of bread; half a bun, bagel, or muffin; 1 oz. of dry cereal; or ½ cup of cooked cereal, rice, or pasta.

BASIC PRINCIPLES AND DIFFERENT METHODS
Most alternative therapists believe that everybody can benefit from dietary self-help for both prevention and treatment of disease. Many therapies recommend fasting, perhaps drinking only fruit and vegetable juices, or eating salads or single fruits. Fasting is probably the oldest therapy known to humankind. Primitive people, and animals, instinctively stop eating when they are ill, probably because digestion takes up energy and puts extra strain on the body. The aim of fasting and dietary therapy is to rid the body of the toxins that are said to accumulate from the wrong diet, so that it can function at its optimum level.

Self-administered fasts should not exceed two days, and returning to eating should be gradual. Start with raw fruit and salads, followed by wholegrain foods, fish, poultry, or lean meat, and then yogurt and dairy produce. Fatty, sugary, and refined carbohydrate foods, coffee, cola, tea, and other stimulants, alcohol, and tobacco should be avoided completely.

Some of the side effects of fasting - such as headache, bad breath, diarrhea, and vomiting - are unpleasant and if they are intolerable, the alternative is to introduce a very little fruit and/or fresh vegetable juice, into the diet.

WHAT CAN DIETARY THERAPY TREAT?
Almost all complementary therapists recommend dietary therapy as part of their treatment, for it works both on a preventive and a therapeutic basis. Specialized diets may be used to treat particular problems, but overall, dietary therapy is aimed at improving general health and well-being. Particular conditions that respond to dietary therapy include:

• Heart and circulatory disorders
• Infections, including fungal infections (i.e. thrush)
• Some cancers
• Digestive problems
• ME
• AIDS and other immune problems
• Allergies and catarrh
• Arthritis and rheumatism
• Sinus problems
• Alzheimer's and Parkinson's diseases
• SPECIAL DIETS

People on therapeutic diets often experience side effects similar to those from fasting. Symptoms commonly become worse before they improve. Modified diets should only be followed for a limited time to avoid vitamin and mineral deficiencies. Infants and children should never be made to fast, or even put on a restricted diet, except under medical supervision.

Exclusion diets - Exclusion, or elimination, diets are used to detect foods suspected of causing food allergies or intolerance, or triggering attacks of illness, such as migraine. Suspected foods are avoided for about two weeks and then reintroduced one at a time.

Vegetarian diet - Vegetarians eat no meat, fish, or poultry, but most eat eggs and dairy products (this is called lacto-ovo-vegetarianism). A vegetarian diet followed correctly over a long period can reduce risk of heart disease, cancer, and other major illnesses.

Vegan diet - Vegans eat no animal products. They need vitamin B12 from fortified foods or supplements. A vegan diet shares most of the benefits of a vegetarian diet when carried out correctly.

Food combining diet - Food combining (the "Hay diet") advises against combining starch and sugar with protein and acid fruits. At least four hours should separate starch and protein meals. Protein, starch, and fats are eaten in small quantities, and all refined and processed foods are prohibited. This diet is said to improve arthritis and digestive problems.

Anti-Candida diet - Anti-Candida diets for the treatment of thrush avoid yeasts and mold - as in malted cereals, cheeses, fungi - sugar and sugary foods, and peanuts.

Liver diet - In a liver diet the following foods are avoided because some alternative therapists believe they are difficult for the liver to process: mean, poultry, eggs, sugars and sugary foods, dairy produce, nuts, coffee, tea, alcohol, chocolate, fried food.

Low blood sugar diet - A low blood sugar diet is based on three meals a day, plus small, two-hourly snacks of nuts or seeds, milk, oatcakes, or whole-wheat toast. Sugar and sugary foods must be avoided.

NUTRITIONAL THERAPY
Nutrients are the chemical components of diet and are essential to life and health. Nutrients are classed as either macronutrients or micronutrients: · Macronutrients are carbohydrates (sugars and starches), fats (including essential fatty acids), proteins (including essential amino acids), and fiber.· Micronutrients are vitamins, minerals, and trace elements that cannot be manufactured in the body, and so must be eaten daily. If micronutrients are absent or too low, illness results.

Micronutrients have only been identified extensively and researched since 1913 when an American biochemist, Elmer McCollum, discovered the first vitamin, vitamin A. Their use in treatment has now become a major, and rapidly growing, therapy in its own right throughout the world. Another nutritional therapy is megavitamin therapy, established by the Nobel Prize winner Dr. Linus Pauling in the United States. He believed that schizophrenia and other mental problems were the consequence of vitamin deficiency and originally called his therapy "orthomolecular psychiatry".

The therapeutic prescription of nutrients is known as nutritional therapy, and practitioners specializing in it are nutritional therapists. Nutrients prescribed in this way are called "dietary" or "food supplements," and they come in the form of tablets, capsules, powders, or liquids. Nutrients may sometimes also be injected for greater effect, but in most countries only conventional medical doctors may do this.

WHAT CAN NUTRITIONAL THERAPY TREAT?
Nutritional therapy aims to find where individual health has become unbalanced, and to put it right using nutrition as a therapy. Most treatment is preventive and restorative, but because it is holistic, many conditions will respond, including:

• Stress and stress-related disorders
• Pregnancy problems
• Arthritis
• Circulatory disorders
• Eye conditions
• Women's problems, including PMS, infertility, PNI, and menopause
• Joint and bone problems
• General infections, including coughs, colds, and influenza
• Cancers
• MND, MS, Alzheimer's and Parkinson's diseases
• Many others