Food Allergy vs. Food Sensitivity: What’s The Difference?

Have you ever had a bad reaction to a food or a beverage? If so, did you know whether your reaction was caused by a food allergy or a food sensitivity?

Unless you’re an expert – like a registered dietitian, a nutritionist or a food researcher – you might use these terms interchangeably. But a food allergy and a food sensitivity are different things, and it’s helpful to know the distinctions, says Bethany M. Doerfler, a clinical research dietitian in the division of gastroenterology and hepatology at Northwestern Medicine in Chicago. She works in the division’s Digestive Health Center.

Food allergies and food sensitivities are different in seriousness, adds Julia Zumpano, a registered dietitian with Cleveland Clinic’s Center for Human Nutrition. “It’s important to know the difference because they are treated differently,” Zampano says. “An allergy can have long-term negative health effects. Sensitivity is more of a nuisance.”

Food allergies can cause life-threatening problems, such as difficulty breathing, whereas food sensitivities may just cause temporary discomfort, says Lisa Jones, a registered dietitian based in Philadelphia.

With food allergies, patients typically have a history of symptoms. An allergy diagnosis can be confirmed with either a blood screening or a skin allergy test. These tests can confirm the presence of immunoglobulin E, or IgE, antibodies which are typical in patients with food allergies. If a patient’s history and allergy tests aren’t conclusive, a board-certified allergist could conduct an exam in which the patient slowly ingests foods that he or she may be allergic to. These tests are conducted in a facility where the health care provider can quickly and effectively treat an allergic reaction.

Food allergy symptoms typically manifest themselves quickly, within 30 minutes of eating a food one is allergic to, says Sonya Angelone, a San Francisco area-based registered dietitian and spokesperson for the Academy of Nutrition and Dietetics.

On the other hand, food sensitivity reactions may be delayed for up to 72 hours, Angelone says.

Allergies to food occur when the immune system recognizes a food component that it identifies as dangerous, Doerfler says. The immune system overreacts by producing IgE antibodies. “These antibodies drive cells to release chemicals, which can (in serious cases) cause swelling and difficulty breathing,” she says. “This is anaphylaxis. Even small amounts of food consumed or touched or breathed in can cause allergic reactions,” Doerfler adds.

Anaphylaxis symptoms, which can range from mild to severe, include:

About 90% of food allergies are caused by nine foods, Angelone says. These nine foods are:

Sesame is the latest food to be added to the list. In April, Congress passed the Food Allergy Safety, Treatment, Education and Research Act of 2021. The legislation adds sesame to the group of major food allergens that must be included on labels.

Some people may also develop an allergy to red meat that’s triggered by a bite from a Lone Star tick. “The bite transmits a sugar molecule called alpha-gal into the person’s body. In some people, this triggers an immune system reaction that later produces mild to severe allergic reactions to red meat,” according to the Mayo Clinic.

Research suggests this tick bite could cause allergies to meats including:

Most cases of this allergy have occurred in the southeastern U.S., where the Lone Star tick is predominantly found, according to the Mayo Clinic. The tick is also found in the eastern and south-central regions of the U.S.

If you have a food allergy, the only way to avoid a reaction is to not eat the foods that cause symptoms, Zumpano says. But sometimes people with allergies come into contact with such foods even when they’re trying to avoid them.

Fortunately, there are effective treatments for food allergy reactions.

If your reaction is minor, over-the-counter antihistamines can be effective, says Dr. Omid Mehdizadeh, an otolaryngologist and laryngologist at Providence Saint John’s Health Center in Santa Monica, California. Such medications can help mitigate some of the symptoms of a relatively mild reaction, such as hives or itching, he says.

More serious allergic reactions, such as severe swelling, difficulty breathing, chest tightness and wheezing should prompt an individual to go to the emergency department, Mehdizadeh says. There, physicians generally use a stronger anti-inflammatory, such as steroids, to help treat the reaction.

People who have a known history of severe allergies should carry an auto-injector device, such as an EpiPen or an Adrenaclick device, he says. These devices provide epinephrine, a medication that is also used in the emergency department to treat a severe allergic reaction. Your health care provider can show you how to use the device properly. Be sure to replace the epinephrine before its expiration date.

On the other hand, food sensitivities and intolerances take place in the digestive system and are usually associated with inadequate digestive enzymes or sensitivities to food additives, Doerfler says.

Common food sensitivity symptoms include:

Some common food sensitivities are:

If you experience symptoms associated with food sensitivity, such as nausea and bloating, consult your primary health care provider. Your provider may refer you to a gastroenterologist. A health care provider may also ask you to keep a food diary to help determine what foods or beverages cause you problems.

If you have a sensitivity to a food or beverage, “avoid the food or drink or have them to a lesser extent to minimize symptoms,” Zumpano says. “You can eliminate the food or beverage for two to three weeks and then resume consuming it in small portions to see what your level of tolerance is.”

Angelone suggests working with a registered dietitian to create a strategy to replace foods that cause you symptoms with other options which offer similar nutritional value. “Often self-directed elimination diets can fail to meet nutritional needs and leave patients feeling restricted,” Angelone says.