Individualizing the Diet

Townsend Letter for Doctors and Patients, Oct, 2001 by Alfred H. Wertheim

The Metabolic Typing Diet

by William L. Wolcott

Doubleday, 1540 Broadway, New York, New York 10036 USA 2000, 428 pp, ISBN 0385496915

The author explains why some people thrive on a vegetarian diet while others feel awful; and some people do well on a high-protein diet while others get sick on it. And some people can lower their cholesterol by reducing their intake of fat, while others find that their cholesterol level drops when they increase their fat intake. The answer to these puzzles is differences in metabolic type. In some people the sympathetic branch of the autonomic nervous system is stronger, while in others the parasympathetic branch is stronger. The following table shows how the two branches affect different parts of the body.

                     Sympathetic           Parasympathetic
                     Branch                Branch
Liver                Releases glucose      Stores glucose
                     (raises blood sugar)  (lowers blood sugar)
Heart                Increases heart rate  Decreases heart rate
Stomach Digestive
 Secretions          Decreases             Increases
Intestinal Mobility  Slows down            Speeds up
Pupils               Dilates               Contracts
Bladder Sphincter    Constricts            Relaxes

Some of the characteristics associated with dominance of one or the other branch are as follows:

  Sympathetic Dominance    Parasympathtic dominance
     predisposes to:           predisposes to:
   High blood pressure         Low blood sugar
        Insomnia             Irregular heartbeat
     High motivation              Allergies
       Infections                 Cold sores
     Poor digestion             Fast digestion
Tendency to be tall, thin    Shorter, wider build
      Hyperactivity            Warm emotionally
      Irritability              Slow to anger

Besides the autonomic nervous system, there are other mechanisms involved in the control of body functions. These include the oxidative system (fast vs. slow oxidizer), catabolic/ anabolic balance, acid/alkaline balance, electrolyte balance, blood type, etc. The author feels that for determining what foods and supplements are best suited for a particular individual, the status of the autonomic nervous system is the most crucial, followed by that of the oxidative system. The author combines these categories and uses the terms Protein type and Carbohydrate type. He has prepared a questionnaire which helps to determine whether a person is a Protein type, a Carbohydrate type, or a Mixed type. The questionnaire consists of only 65 questions, whereas the ones used by testing organizations consist of hundreds of questions, Apparently the author believes that his 65 questions are the most relevant to determine basic metabolic categories.

Metabolic typing takes cognizance of the fact that each individual is different and has different nutritional requirements. Part of this is due to heredity. For example, Eskimos thrive on large quantities of fat and meat, while the natives on some Pacific islands thrive on an almost total vegetarian diet. Very few people in the United States are pure Sympathetic types or pure Parasympathetic types. However, by carefully answering the questions it becomes possible to determine whether one branch of the autonomic nervous system dominates.

Protein types will do best on a high-protein/high-fat diet. This would include meat (beef, organ meats, veal), fish (salmon, tuna, herring, sardines, anchovies), poultry, eggs, cheese, yogurt, nuts and seeds. Preferred vegetables are asparagus, celery, spinach, winter squash, carrots, cauliflower, peas, lentils, and artichokes. Other foods include avocados, olives, mayonnaise, nut butters and olive oil. Fruit and fruit juices should be restricted, especially citrus juice. Items to be avoided are alcohol, caffeine and sugar. Supplements which may be needed include calcium, phosphorus, choline, inositol, bioflavonoids, vitamins A, B5 and E. Most Protein types need to eat snacks between meals.

Carbohydrate types do best on a low-fat/low-protein (low-purine) diet. This would include some light meat (chicken breast, turkey breast, Cornish game hen), light fish (flounder, haddock, halibut, perch, scrod, sole, trout, white tuna), low-fat cheese, low-fat yogurt, low-fat cottage cheese, whole grains, brown rice, millet, buckwheat, most vegetables and all fruits. Nuts, nut butter, seeds, oils, butter, cream and other fats must be used sparingly. Since calcium intake should be minimized, the use of dairy products may need to be restricted. Supplements which may be needed include magnesium, zinc, potassium, chromium, manganese, vitamins B1, B2, B6, and folic acid.

Although blood type is not a primary aspect of metabolic typing, the author includes a list of foods that should be avoided, depending on a person's blood type. For example, Type A and Type AB should stay away from soybeans, and Type B and Type O from chocolate, People with digestive problems, irrespective of metabolic type, should avoid the following combinations: