Return
to Menu Page Return
to Menu PageAIDS. AIDS is a chronic disease characterized by progressive decline in immunocompetence. Because many vitamins and nutritional supplements are biological response modifiers that have been shown to stimulate or enhance immune response, the potential areas of fruitful research in this area are limitless.
There is at least preliminary evidence that vitamin A or beta-carotene (its precursor) decreases the immune deficiency that results when animals are exposed to a wide variety of immunocompromising conditions such as trauma, infection, irradiation, and treatment with cytotoxic agents (Seifter et al., 1982, 1983a, 1983b, 1984). There is evidence suggesting that vitamin A supplementation in immune-compromised individuals may be necessary to replace a vitamin A deficiency caused by HIV infection (Lack et al., 1993; Semba et al., 1993). Many other vitamins and nutritional supplements that have been shown to affect immune status also may be potentially potent tools for fighting this deadly infection. This area is ripe for intensive research.~Cancer. It is well accepted that cancer and its treatment can cause malnutrition and that malnutrition itself predicts a poor outcome (DeWys et al., 1980). In general, however, oral dietary treatments for cancer have not been evaluated by mainstream medicine for the possible prevention of malnutrition or for the possible effect on the course of the disease in cancer patients. There are no nutritional recommendations per se for the cancer patient in mainstream oncology (Office of Technology Assessment, 1990), and no diet is currently recommended publicly by NCI or the American Cancer Society for use in cancer treatment. Those nutritional support measures that are offered usually come only after patients have reached advanced stages of cancer and have become malnourished, often as a result of side effects of their treatment (e.g., chemotherapy) (American College of Physicians, 1989; Shike and Brennan, 1989).
Little is understood about the nutritional requirements of cancers. However, there is growing evidence that many types of tumors have an increased need for iron in order to grow (Elliott et al., 1993; Weinberg, 1992). Red meat is one of the best sources of iron, and iron from red meat continues to be absorbed even if body stores of iron are plentiful (Ascherio and ~Willett, 1994). Therefore, there is at least a theoretical basis for proposing that cancer patients eat a primarily vegetarian diet to slow the growth of their tumors. Furthermore, although the epidemiological data provide solid support for recommendations to consume an abundance of vegetables and fruits or vitamin supplements to prevent cancer, there is a need for research on the effects of such nutritional interventions on individuals who already have cancer. Immunological parameters such as certain immune cell activity or levels of certain cytokines (immune-cell-activating compounds) would provide information about whether such diets do or do not increase the body's ability to attack cancer cells.
The 1990 OTA report Unconventional Cancer Treatments suggested that at least certain aspects of most of the unconventional dietary regimens for cancer it reviewed (e.g., intake of fresh fruits and vegetables and reduction or elimination of sodium and fat) are consistent with current Federal dietary recommendations about reducing the risk of contracting certain types of cancer and other illnesses (Office of Technology Assessment, 1990). The controversial aspects of these therapies, according to OTA, is the idea that dietary treatment can cause the regression of cancer. It is possible that the earlier such dietary regimens are begun, the ~more effective they are. It would be informative to look at various aspects of some of these regimens to determine whether they conform to basic biochemical and immunological research relating micronutrient manipulation to improving immune function or the inhibition of cancer cell growth. For example, Simone (1983) suggested that coffee enemas may increase absorption of vitamin A. There is evidence that vitamin A may play a vital role in boosting immune function (see the section on orthomolecular medicine in this chapter). The Gerson diet is estimated to provide approximately 100,000 IU of vitamin A daily (Seifter, 1988). Further studies are needed to confirm the ability of such measures to increase the absorption of micronutrients.
Heart disease and diabetes. Studies such as those using fat-restricted or fat-modified diets (i.e., intake of greater amounts of monounsaturated fats) have produced quite credible evidence suggesting not only that cardiovascular disease may be stabilized through such methods, but also that death rates from cardiovascular disease can be greatly reduced. Dietary intervention for coronary heart disease may find broader application if attempts are made to further both clinical research and use. A systematic review of the literature, broader ~clinical evaluations, and the development of clinical guidelines could lead to general acceptance. Efforts to disseminate information and transfer technology may be essential. Cost comparisons with conventional treatments may be instructive.
The following are specific areas that are likely to yield fruitful results:
• Sufficient evidence now exists to compel larger scale, multicenter, randomized clinical trials of modified diets such as the Ornish regimen, the Mediterranean-type diet, and high-soy-content diets.
• Dean Ornish's program relies heavily on relaxation techniques as well as fat restriction. It would be informative to know which aspect of his regimen contributes most to the regression of heart disease. If the relaxation component turns out to be a significant factor, this knowledge could potentially save the overall health care system billions of dollars.
• The Pritikin diet and other diets that require low fat, low cholesterol, high fiber, and high ~complex carbohydrate consumption should be tested and evaluated (in terms of all their components) for the treatment of adult-onset diabetes. Even if a small percentage of the nation's 11 million diabetics could control their disease with diet, the savings--in health improvement, delayed mortality, and financial costs--would be enormous.
Food allergies. Despite the large body of literature on food allergies, there is still a need to further study the approach taken by environmental medicine in a variety of other conditions commonly encountered. A mechanism similar to that proposed for arthritis has been proposed in asthma, ulcerative colitis, migraines, hyperactivity, recurrent infections, and other common conditions. The testing techniques need further validation, as does treatment with immunotherapy, environmental control units, and basic biochemical understanding of the causes of chemical hypersensitivity and other "20th century" diseases.
More work needs to be done in the area of food intolerance and neuropsychiatric disorders. Egger and colleagues (1992) have recently implicated an immune system effect as being the mechanism by which incriminated foods produce hyperactivity. Work from other ~investigators is sorely needed.