The advice is less applicable to individuals whose nutritional needs may not be met by these recommendations and whose health may be at risk if they follow the food selection advice. A skillful nutritional therapist will know the guidelines as one way to organize food selection but will also know the many exceptions to these rules and use other methods of diet design such as the Alpha Nutrition Program. Five of the ten leading causes of death in the USA are clearly related to wrong food choices. Changing patterns of food-related illness are recognized. The improvement in the diversity and availability of foods has been a mixed blessing with major problems emerging to negate the potential benefits.
Food is the most intimate part of the environment because food is ingested.
When something goes wrong, it makes good biological sense to look at the flow of substances through the mouth for the source of the problem. Adverse reactions to food are common and produce many disturbances by a variety of mechanisms. Diagnosing adverse reactions to food is an important task of clinical medicine and needs to be taught in medical schools. Often, the potential benefits of diet revision in the solution of health problems are ignored. Many food and nutritional issues are complex and genuinely difficult to understand.