" Upon repeated exposure the severity of the reaction may increase." (https://www.hopkinsmedicine.org/health/conditions-and-diseases/allergies-and-the-immune-sy

" Upon repeated exposure the severity of the reaction may increase." (https://www.hopkinsmedicine.org/health/conditions-and-diseases/allergies-and-the-immune-system https://www.hopkinsmedicine.org/health/conditions-and-diseas...) "After primary sensitization, the allergic immune response is boosted with repeated exposure" (https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4414527/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4414527/) Lots of other things can effect sensitivity/severity too including age, stress, hormones, etc. That's why if you're going to try to increase your tolerance to something you're allergic to through exposure it should always be done under the care of a doctor who will explain the risks, including the risk that your allergy becomes worse and your sensitivity to it higher. If the exposure isn't being done under observation you'll likely be given an epi pen. Desensitization therapy can help some people, but because of the risks it's often done for people who already have severe reactions and it can require a potentially lifelong commitment to taking some daily amount of the allergen in order to keep the benefits. It's not for everyone, but I wouldn't tell someone not to at least look into it with their doctor, especially with foods that are very hard to avoid.