Is It Possible to Be Allergic to All Starches?

Experiencing painful or scary food allergy symptoms can make you afraid to eat anything. If you’ve had a reaction to a starchy food like corn, peas, potatoes, or grains, you might be tempted to limit your diet to avoid risking another reaction.

While it’s possible to have a “true” allergy to starchy foods, it’s actually the proteins in those foods that the body develops antibodies to, triggering allergic reactions, according to the Cleveland Clinic. With antibody-triggered allergies, it’s possible to be allergic to proteins in similar foods, according to Henry Ford Health. But that means it’s unlikely you’d be allergic to every protein in all the different types of starchy foods. For example, a potato allergy is unlikely to cause a cross-reaction with wheat, according to The Doctors Laboratory, a clinical lab services provider in London.

If you have unpredictable reactions to various foods that cause allergy symptoms, it could be a sign of an immune disorder like mast cell activation syndrome (MCAS), says Kara Wada, MD, an allergist and immunologist in Columbus, Ohio. In MCAS, the immune cells responsible for allergic reactions don’t function correctly, leading to symptoms from any number of triggers, says Lisa Klimas, a microbiologist and molecular biologist in Boston who researches mast cell disorders.

Two distinct conditions commonly cause reactions to food with allergy symptoms: “True” allergies, which are triggered by antibodies, and MCAS, in which a dysfunctional immune system reacts inappropriately to a variety of triggers.

When you have an antibody-triggered allergy, you experience a reaction every time you consume the food, and you need to eliminate it from your diet, according to the Cleveland Clinic. But with MCAS, you may react to the same food one day and not the next or suddenly develop new food triggers, Dr. Wada says. This means that trigger foods can often be reintroduced, though it’s not always possible, Klimas says.

If you opt to completely cut starches out of your diet, you’re likely to miss out on key micronutrients and fiber. The B vitamins (other than vitamin B-12) are usually found in whole-grain cereals, according to the Mayo Clinic. Vitamin A is found in many starchy fruits and vegetables like bananas, carrots, and sweet potatoes, according to the National Institutes of Health (NIH). Certain minerals, including zinc, are also found in starchy foods like oats, brown rice, and lentils, according to the NIH. Magnesium, another mineral, can be obtained by eating black beans, potatoes, kidney beans, and white rice, according to the NIH. Eat a varied, nutrient-dense diet of foods you can tolerate. Talk to your doctor or a registered nutritionist about whether you should supplement with vitamins if your diet is restricted.

Before severely restricting your diet, see an allergist to determine the exact cause of your symptoms. A registered dietitian can work with you to come up with an eating plan that fits your specific requirements. Living with antibody-triggered allergies or MCAS can make planning meals more difficult, but having support helps ensure you meet your nutritional needs.

Getting familiar with food labels and experimenting in the kitchen can make eating enjoyable again. Trust your body and don’t be afraid to try new foods that work for you. When dining out, do your research and, if necessary, ask to speak to the chef to get the information you need.