Some people who have an allergy to peanuts undergo therapy to try to get rid of it, but a new study suggests that makes the problem worse. Oral immunotherapy involves taking small but increasing amounts of the allergen over a long period of time so that, in theory, the immune system stops responding to, stops causing an allergic reaction.

The study, out of York University and published in the Lancet, shows that people allergic to peanuts who undergo this kind of therapy are more likely to subsequently have allergic, and even deadly allergic reactions (anaphylaxis) than are those who do not have the therapy.

Fear of a life-threatening allergic reaction can cause great anxiety and affect a person’s quality of life. (iStock)

Avoidance is the best strategy for those with peanut allergies

The authors of the study note that there may be some positive effects of oral immunotherapy observed in the clinic, but this outcome does not translate into …less allergic reactions and anaphylaxis” in the real world. “Instead, the opposite outcome occurs, with more allergic and adverse reactions with oral immunotherapy compared with avoidance of placebo.”

So, the authors recommend people with peanut allergies avoid peanuts rather than undergoing oral immunotherapy. And they say more study is needed.

There are several kinds of foods that may trigger a dangerous allergic reaction. (iStock)

Food allergies increasing worldwide

Food allergies are a growing problem around the world. In Europe and North America, up to eight per cent of children and two-to-three per cent of adults are allergic to some kind of food. While an allergy to milk or egg is often outgrown, an allergy to peanuts lasts for life in 80-85 per cent of cases.

Food allergies can be unpredictable and, in some cases, life-threatening, and that causes much anxiety and can impair a person’s quality of life.

A peanut is not a nut. It is a legume. People may be allergic to both.