Allergic Reactions- How Much is Enough?

How Much of a Specific Food Allergen Will Trigger An Allergic Response? New Study Sheds Light. ~ Guest Post by Kathy Penrod

For many children who suffer from food allergies, the only way to prevent an allergic reaction is to stick to a diet that strictly avoids the allergen. Strict avoidance is necessary because allergic reactions to food allergens can vary by individual. The severity of the reaction in the same person may be different each time he or she is exposed and the level of the allergen that causes a reaction can also vary. The uncertainty that surrounds food allergy reactions often causes food-allergic children and adults to be wary of even trace amounts of an allergen present in food, on surfaces and in air particles. That uncertainty, coupled with unclear food labeling practices, often causes fear about eating prepackaged foods, even when those food items should be safe.

One example of this phenomenon occurs when a food item does not contain any allergens in its listed ingredients but is manufactured in a location that also manufactures food that does contain the allergen. These food items sometimes carry a label that states the food item “may contain” an allergen. So the question then becomes, is the food safe to eat or not?

Photo courtesy of Jacionline

Finding Clarity

But what if food-allergic children and their parents could determine how sensitive they were to an allergen and what level of the allergen would cause an allergic reaction? Professor Claire Mills and a team of researchers from the Institute of Inflammation and Repair at the University of Manchester, located in the United Kingdom, have been working on a solution to help bring clarity and consistency to the issue.

The team recently conducted a study to determine the level of allergen that would produce a reaction in only 10 percent of the most sensitive allergy sufferers. Five allergens were examined: peanuts, hazelnuts, shellfish, finned fish and celery. The study was printed in the January 2015 edition of the Journal of Allergy and Clinical Immunology.

As part of the study, Professor Mills and her team enlisted participants to engage in a food challenge in which they ate small amounts of foods they were allergic to.

photo courtesy of Healthline

Allergic reactions occur when the immune system malfunctions in the presence of an allergen. Normally, the immune system protects the body from harmful substances like viruses and bacteria. But when the immune system malfunctions in the presence of certain food proteins, it responds inappropriately to the food protein, a substance most people's bodies perceive as harmless. Consequently, the body overproduces chemicals called histamines, which cause allergy symptoms like runny nose, itchy and watery eyes or swelling. Allergies may appear as external or internal symptoms and in any part of the body.

  

Researchers closely monitored the participants’ allergic reactions and found what appeared to be baseline levels of the five foods, which would cause a reaction in the 10 percent of participants who were most sensitive to food allergens. In other words, the participants who were most sensitive to the allergens reacted at specific levels of allergen proteins. The results showed the following levels of allergen proteins were needed to trigger a reaction:

·         1.6-0.1 mg of peanut, hazelnut or celery protein

·         27.3 mg of finned fish protein

·         2.5 mg of shellfish protein

The theory is that if the person is most sensitive to allergens react at a certain level, anything less than that level would be safe for food-allergic people to eat. Although the implications may be compelling, there is no information on how the researchers identified the people most sensitive to food allergens or how their levels of sensitivity varied from others who are less sensitive to food allergens.

Moving Forward

While the study was small, the intent was to move toward helping people become better informed of their own sensitivities to particular allergens and to help improve packaged food product labeling.

The study and its findings are focused on Europe and the European populations but have implications for the United States. The research is promising, but more large-scale studies are needed.

What are your thoughts? Please feel free to share your opinions & comment.

A little about the author

Kathy Penrod is the founder of My Kid's Food Allergies—a website dedicated to keeping children with food allergies safe and healthy through education and awareness. The goal is to create and maintain a site that provides the best and most recent information about food allergies, a community of parents and other adults interested in learning and sharing about food allergies and access to physicians and other food allergy experts.