Most people know someone with a food allergy. According to Food Allergy Research and Education (FARE), about 33 million people in the U.S. have food allergies, including 1 in 10 adults and 1 in 13 children. The prevalence is rising. While most food allergies develop in childhood, they can occur at any age, and adults can even develop new allergies later in life. Almost half of adults with food allergies report developing at least one during adulthood. Older adults should be aware of food allergies because symptoms can be worsened by a weakened immune system or masked by other health issues, and the consequences can range from uncomfortable to life-threatening.
A food allergy occurs when a person’s immune system overreacts to something in a food, usually a protein the body thinks is a threat. Symptoms can range from mild to life-threatening and affect different body parts. They can include an itchy or runny nose, sneezing, an itchy mouth, swelling of the tongue or lips, hives, itchy skin, nausea, vomiting, diarrhea, shortness of breath, wheezing, tightening of the throat, trouble breathing or swallowing, a drop in blood pressure, weak pulse, and feeling dizzy or faint. Symptoms can be unpredictable, with different symptoms or levels of severity from one reaction to the next. Anaphylaxis is a serious allergic response involving more than one body system, such as the skin, gastrointestinal system, respiratory tract, and/or cardiovascular system. It often involves swelling, hives, lowered blood pressure, and can lead to shock in severe cases. Anaphylaxis can occur immediately or a few hours after exposure to an allergen, so it’s important to monitor closely. Anaphylactic shock needs immediate treatment, typically with epinephrine, or it can be fatal.
Nearly 90% of food allergies are caused by nine foods: shellfish, milk, peanuts, tree nuts, eggs, fish, wheat, soy, and sesame.
Nearly 90% of food allergies are caused by nine foods: shellfish, milk, peanuts, tree nuts, eggs, fish, wheat, soy, and sesame. Adults are most commonly allergic to shellfish, milk, peanuts, and tree nuts. Even small amounts of these allergens can cause reactions in sensitive individuals. Recognizing these common allergens and understanding where they appear in meals is crucial for managing risk.
Another growing food allergy is alpha-gal syndrome, which begins with a tick bite and affects about 450,000 people in the U.S. In alpha-gal syndrome, tick saliva introduces a carbohydrate (galactose-α-1,3-galactose) that triggers an immune response after eating mammalian meat like beef, pork, lamb, venison, or mammal-derived ingredients like dairy and gelatin. The lone star tick is most often linked to alpha-gal syndrome, but other ticks can also cause cases. Preventing tick bites is the first step in protecting against alpha-gal syndrome.
Food allergies are often confused with food intolerances. A food allergy is an immune system response usually involving the IgE antibody which can lead to life-threatening reactions. Food intolerances, on the other hand, do not typically involve the IgE antibody and primarily cause digestive symptoms like bloating and diarrhea. Lactose intolerance, for instance, occurs when the body lacks the enzyme to digest milk sugar, causing bloating and diarrhea but not life-threatening reactions. Celiac disease, a reaction to gluten in wheat, rye, and barley, is also not considered a true food allergy. It does not involve the IgE antibody, although it does involve IgA/IgG antibodies, damaging the small intestine lining and causing symptoms like bloating, gas, diarrhea, constipation, headaches, itchy skin rash, and mouth sores. If you experience symptoms after eating a food, consult an allergist. Testing methods like skin prick tests, blood tests for IgE antibodies, and supervised oral food challenges can help confirm whether you have an allergy.
Exposure to allergens can happen in obvious and subtle ways. Eating the allergen is the most direct form of exposure. Inhaling vapors or particles, such as when cooking shellfish, can trigger reactions in some people. Cross-contact during food preparation is another major source of accidental exposure. This can happen if surfaces like a cutting board or counter aren’t cleaned between uses, utensils or knives aren’t thoroughly washed, or someone handling your food has touched the allergen and not washed their hands. Even small amounts transferred this way can be enough to cause a reaction.
Living safely with food allergies involves vigilance and preparation. Some key strategies recommended by FARE include:
- Avoid the allergen completely.
- Read ingredient lists carefully. Food labeling laws require that the top nine allergens are listed clearly on packaged foods, but be aware of potential hidden sources in sauces, dressings, and baked goods.
- Communicate when eating out. Always inform your server that you have a food allergy and ask how foods are prepared. Shared equipment or fryers can present a risk.
- Prevent cross-contact at home by using separate cutting boards, knives, and utensils for allergen-containing and allergen-free foods. Wash hands, dishes, and surfaces thoroughly with hot, soapy water after contact with allergens.
- Have an emergency plan. Work with your healthcare provider to create an action plan. Keep prescribed medications, such as epinephrine auto-injectors, readily available and ensure family members know how to use them.
- Educate those around you. Let friends, caregivers, and family members know about your allergies and the importance of preventing exposure.
Food allergies require lifelong attention, but understanding the basics can help you stay safe and healthy. Older adults may have unique risks due to other health conditions, medications, or social situations where they rely on others for meal preparation. By learning to recognize allergens, differentiate allergies from intolerances, and prevent accidental exposure, you can enjoy meals with confidence and minimize risk. For more information, resources, and support, visit Food Allergy Research and Education at foodallergy.org.
