A report from Israel last year indicated that among 22 patients with poorly controlled asthma, 15 improved remarkably within weeks after avoiding all dairy foods. When the 15 patients were then challenged with dairy products, five had a recurrence of severe asthmatic attacks.
When off dairy products, the patients reported a sensation of breathing relief, a decrease in medication needs and no need for hospital care. More evidence of food sensitivity.
Digestive allergies tend to defeat the scientific clinician. Respiratory allergies (grass and pollens), however, are duck soup. They are associated with skin reactions that can be demonstrated by testing. Most food allergies do not, and, while blood tests for food allergies continue to be developed, those presently available have proven to be inaccurate and unreliable.
Studies on 10 asthmatic kids in England who gave a history of sometimes but not always wheezing after a gulp or two of cola drinks have shown how tricky the unraveling is going to be.
The researchers used histamine as a co-challenge agent. It is a natural product of body tissues that is released by cells along the airway when triggered by an allergic reaction. Histamine produces the spasm that causes the wheezing. In their study of the kids, histamine was delivered into their airways through an aerosol spray, then they drank various amounts of cola as a challenge.
The study demonstrated a need for an interplay between histamine release and cola challenge for symptoms to be produced. Histamine and cola always produced a response, whereas cola alone did not, but the degree of wheezing varied in the same patient from visit to visit.
It is this will-of-the-wisp characteristic of food allergies that so frustrates efforts to understand and better manage the problem, a characteristic that has led to uncertainty about whether allergy is the correct term for the reactions of these patients when exposed to food; hence the preferred and broader term, food sensitivity.
The best hypothesis at present is that individuals suffering peculiar reactions to food have some kind of membrane barrier problem that allows food or its reaction products to get into their bodies to cause symptoms. Such patients suffer a failure of the integrity of a frontier, the surface of their digestive tract, a surface that interfaces with their food environment. That gut surface is a sheet of mucus-secreting cells with a huge total area, measured in acres. Its integrity may be faulty some of the time or most of the time or only on rare occasions when circumstances of stress or debility dictate.
Sensitivity to the reaction products can express itself as the wheezing of asthma or a headache, depression, muscle pains or skin rashes.