Tasty Enemies: Everything You Need to Know About Food Allergies

May 15, 2019

Living with a food allergy can make every meal seem like a project. Food allergies can develop at any age, and may be life-threatening. If you or a loved one suspect a food allergy, it’s important to get an accurate medical diagnosis, so that you don’t avoid the wrong foods unnecessarily and are prepared to treat a reaction, if and when it occurs.

Dr. Paul J. Berlin, board-certified allergist and immunologist on the medical staff at Jefferson Health in New Jersey, explains what causes food allergies, as well as how they are diagnosed and managed.  

An allergen is any substance that triggers the immune system to release antibodies and the chemical histamine, resulting in a physical reaction. Symptoms of an allergic reaction may include itchiness, swelling, hives, diarrhea, and abdominal pain. In some cases, these symptoms will become severe enough to cause anaphylaxis.

Allergic reactions to food often depend on the state of your immune system. Someone who is allergic to eggs may experience different reactions to eating them on separate occasions. An allergic reaction may worsen if you’re fighting a cold or other ailment.

“Why this reaction occurs in some people, but not in others, is still difficult to answer,” said Dr. Berlin. “Years ago, the protocol was to avoid giving babies and young children highly allergenic foods, such as peanuts, tree nuts, soy, and shellfish. We now know that the body is much more immune when it is immature, and consuming these foods promotes tolerance later in life.”

Other common food allergies include milk, wheat, fish, corn and garlic.

Dr. Berlin explains that food allergies can also result from another substance being closely intertwined with that food, saying, “My wife has tree and grass pollen allergies, and during this time of year, if she eats an apple, her mouth will start to swell.”  

Because allergic reactions are either immediate or delayed (taking hours or even days to occur), and because most people have diverse diets, diagnosing a food allergy is tricky.

“When someone eats five different foods, and their face swells, how do you know what caused it?” asked Dr. Berlin. “We look for signs of other allergies and intolerances. Then we proceed to look at each food during a food challenge.”

“Blood tests and skin tests for food allergies are notoriously inaccurate,” continued Dr. Berlin. “Instead, we introduce small amounts of the suspected foods into the patient’s body, and observe their reactions over time. This is always done in an environment equipped to handle allergic emergency.”

It’s unsafe to try this, or similar “tests,” on your own. Elimination diets can be especially dangerous, because they deprive the body of many nutrients.

Sometimes, a reaction to food may not be an allergy, but intolerance, which impacts the digestive tract, not the immune system. Food intolerances are typically easier to manage than allergies. They result from the lack of a specific enzyme needed to properly digest that food. However, other foods may be available that supplement the enzyme.

When it comes to managing your allergy, first things first – an accurate diagnosis. Outgrowing a food allergy is possible, so if you’re curious about whether or not you’re still allergic to a food, it helps to see an allergist.

“After diagnosis, avoidance is key,” said Dr. Berlin. “But you need to know exactly what you’re consuming. Don’t assume that meals prepared at a restaurant, or even by a friend, are going to be safe. Education through reading other people’s stories online can be extremely beneficial.”

The other necessary means of managing your food allergy includes knowing how to administer your medication, when needed.

Studies are being done to develop medications that will help lessen the impact of allergenic foods. Until then, management of food allergies will take the time and effort of people affected, as well as the awareness and understanding of people around them.

To learn more about food allergies, visit