Food allergies occur in many patterns and often cause chronic disease.

Commonly quoted "expert" opinions tend to minimize the incidence and importance of food allergy. While the dogma is misleading, it represents vested interests and is remarkably persistent.

The problem is not that 25% of people recognize symptoms from food ingestion, but that many more people do not recognize that food is making them ill. We hope the reader will take the time to find out why we think food allergy is such an important mechanism of disease and how to resolve common food-related health problems by diet revision.

The original concept of allergy included all immune-mediated disease and the term allergy was interchangeable with the term "hypersensitivity." An clinical immunology text will take the approach that allergy and autoimmune disease are the two major categories of hypersensitivity disease. If the term "Food Allergy" refers to all interactions between molecules derived from the food supply and the immune system, then many hypersensitivity disorders fall into the category of food allergy. The spectrum of clinical manifestations of food allergy can only be understood if different patterns of food allergy are allowed.

Allergy can be thought of as hypersensitivity disorders with external causes. Internal hypersensitivity disorders are thought of as autoimmune diseases. Although disease descriptions pretend there are distinct boundaries between inside and outside and tend to ignore body-environment interactions, it is unlikely that distinct inside or outside diseases exist. The human body is in continuous relationship with the environment and a constant molecular stream connects inside and outside. A better assumption is that autoimmune disorders have inside, self-perpetuating causes as well as outside factors such as ingested drugs and food materials. Food materials should be given priority consideration since this is the biggest chunk of the environment to get inside and to interact with immune networks.

Immediate and Delayed

The first distinction that recurs in the literature is between immediate and delayed patterns of food reactivity which loosely correspond to IgE-mediated allergy and non-IgE mediated responses. Many authors refer to the original four categories of immune-mediated injury defined by Gell and Coombs. The definition of food allergy broadens to encompass any of these immune-mechanisms, in any combination. The concept of four mechanisms is just a starting point for understanding immune-mediated disease. These very complicated defense-injury sequences cause a variety of disease states. Businco et al reviewed food allergy in infants and children.and stated:

"Food Allergy may be defined as a complex of clinical syndromes resulting from the sensitization of the patient to one or more foods, in which symptoms manifest locally in the GI tract or in remote organs as a result of immunologic reaction. At the beginning of the century Hamburger and Schloss documented the first known cases of FA. Since then a vast array of symptoms and disorders have been attributed to the ingestion of some foods. It is virtually impossible to list the constellation of symptoms that may be due to FA."

Knowledge of the nature and mechanism of adverse reactions to foods is limited. Uncertainty about mechanisms of food reactions continues into the community where many improvised and questionable tests and treatments for food allergy or "food sensitivity" have become popular. The relative neglect of food factors in medical practice creates interesting blind-spots in the handling of patients and the understanding of disease. A major shift of popular interest in food problems, however, has created a need for better informed physicians who are ready to grapple with the real-life issues of food, eating, and the multifaceted problem of adverse reactions to food. The subject of food allergy has never assumed the importance that it is due.

Delayed patterns of food allergy are not obvious and generally go unrecognized. Symptom onset is delayed many hours after eating foods and chronic disease is often the result.

Many of the major unsolved disease of our civilization are either degenerative and/or inflammatory and many are recognized to be immune-mediated or hypersensitivity diseases. The delayed patterns of food allergy can be the cause of chronic and disabling hypersensitivity disease. The stakes are high both for individual patients and for the society as a whole. None of the common hypersensitivity diseases have been solved and most appear to rage on, afflicting increasing numbers of patients with chronic and disabling diseases. Asthma, allergy, rheumatic diseases, autoimmune diseases, multiple sclerosis, diabetes, thyroiditis, psoriasis are examples of hypersensitivity diseases which involve humoral and cell-mediated immunity. We use celiac disease - wheat allergy- as a prototype which demonstrates the prolific ability of food allergy to produce a wide range of diseases.

We believe that delayed patterns of food allergy may afflict more than 100 million Canadians and Americans. This may seem to be an outrageous assertion, but if you examine the lengthening list of immune-mediated diseases without explanation or successful therapy - you have to be interested in this theory.