Most food allergies start in childhood, but that doesn’t mean you’re in the clear. Protect yourself by staying proactive and informed.
Food allergies are a big topic among children and their parents, but they’re something that should be on your radar too.
Today, nearly 15 million Americans have at least one food allergy. And according to recent research from Northwestern University Feinberg School of Medicine, about half of adults with food allergies first experienced them after the age of 18.
“You can develop a food allergy at any age,” says Flavia Hoyte, M.D., an allergist and immunologist at National Jewish Health in Denver, which specializes in immune system research. In other words, you may have eaten a food your whole life with no problems and then suddenly develop an allergy to it.
Scientists aren’t exactly sure why this happens, and research on food allergies in adults is a fairly new area. But one factor for older adults: As we age, so does our immune system (it’s called “immunosenescence”), which causes cells to start reacting differently to certain stimuli, including foods.
What Causes Food Allergies?
Allergies are the result of a reaction that starts in your immune system, according to the American Academy of Allergy, Asthma, and Immunology (AAAAI).
If you have an allergy to a certain food, your immune system mistakenly identifies a protein in that food as an invader, and sends antibodies to kill it. It can cause symptoms like:
- Anaphylaxis, a potentially life-threatening reaction characterized by wheezing, throat or chest tightness, or trouble breathing
According to AAAAI, 90 percent of food allergies are caused by these common allergens:
- Shellfish: More common in adults
- Fish: More common in adults
- Peanuts: More common in adults
- Tree nuts: More common in adults
- Cow’s milk
Most food allergy symptoms happen within two hours after eating, says Dr. Hoyte, so you should know pretty quickly if your body isn’t reacting well to something you’ve eaten.
You don’t need to have a major reaction to be considered allergic. If you notice something as minor as an itchy throat or intestinal discomfort after consuming any of the foods above, flag it for your doctor. If you experience any signs of anaphylaxis, seek medical help right away, or take emergency medication (more on that below).
How to Determine If You Have a Food Allergy
The only way to confirm a food allergy is via medical testing: skin prick tests, blood analysis, or an oral food challenge, where your doctor will feed you incremental dosing of a food and observe how your body reacts.
Do not try to self-diagnose—you don’t know how you’ll react. Plus, other conditions mimic the symptoms of a food allergy.
If your doctor confirms that you have an allergy, you’ll need to avoid that food as much as possible. Your allergist will also likely prescribe an epinephrine auto-injector like an EpiPen to keep with you. If you ever have a severe allergic reaction, the EpiPen can deliver a shot of epinephrine (a.k.a. adrenaline) to immediately open your airways and reverse other effects.
Also essential: Make sure your loved ones and friends are aware of your allergy, and know where to find your auto-injector should you ever be incapacitated.
“Never leave home without it,” says Dr. Hoyte. “It can’t help you there.”
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