Information from AAFA’s Ask the Allergist is not a substitute for a consultation with a health care professional. Always talk with your own doctor before making changes to your asthma or allergy management plan.

This question appeared in our spring/summer 2020 issue of freshAAIR Magazine, our FREE digital magazine featuring news and resources on asthma and allergies. Read the most recent issue.

Question: If you haven’t eaten a food in a couple of years and then try it again, does that increase your chances of developing an allergy to that food? Is it possible for a first allergic reaction to a food to be anaphylaxis? (Anaphylaxis is a severe allergic reaction that can be life-threatening.)

Answer: For an adult, the risk would be very low, but it is possible. For adults, new food allergy triggers are more likely to be nuts and seafood. For young children, it is possible to have an allergic reaction the first time they eat the food. This is one of the reasons allergists recommend early exposure to peanut in the first year of life for those who are at a higher risk (children with an egg allergy and severe eczema). In this case, eating the food regularly helps lead to food tolerance and a decreased risk of allergic reactions.

Dr. Douglas Johnston is our Ask the Allergist columnist. Dr. Johnston is a board-certified allergist/immunologist with Asthma & Allergy Specialists, P.A., in Charlotte, North Carolina. He obtained his D.O. from New York Institute of Technology College of Osteopathic Medicine. He completed his residency at Winthrop University Hospital in Mineola, New York. Dr. Johnston grew up with both allergies and asthma. He decided it would be exciting to help people with these conditions. His passion about food allergies also comes from having a child with a peanut allergy.