Is It a Food Allergy or an Intolerance? 

Food usually brings people together in friendship, in celebration, even in sorrow. But it can also be a major source of stress. 

For some, a single bite of the wrong food can mean a trip to the emergency room. This is called anaphylaxis, a classic food allergy reaction. For others, eating a meal with certain ingredients can trigger a day in the bathroom. That type of reaction is more likely to be a food intolerance. 

Sometimes, an allergic reaction can manifest in the same way as a food intolerance – which is why it’s so hard to accurately self-diagnose your problem. If you suspect you have food allergies, consider getting tested by an allergist. Your MDVIP-affiliated provider may be able to provide answers, too. 

In the meantime, we can help you learn more about the big differences and subtle distinctions between a food allergy and a food intolerance. 

Allergic Reactions Occur in Different Parts of Your Body 
When you have a food allergy, the problem starts in your immune system. When you have a food intolerance, the problem likely starts in your gut. 

Let’s start with a look at food allergies. If you eat an offending food, your body mistakes it as an unwelcome invader and starts producing immunoglobulin E (IgE), antibodies. They’re special proteins designed to target and eliminate the troublesome substance. A high level of IgE on a blood test can help your doctor diagnose a food allergy. 

In general, food intolerance does not cause elevated IgE. It stems from an inability to properly digest a given food. For example, if you have lactose intolerance, your gut doesn’t produce enough lactase, an enzyme in dairy products that helps break down the naturally occurring sugars in milk.

Food Allergies Can Be Fatal; Food Intolerances Are Not 
Food allergies and food intolerances can both cause gastrointestinal (GI) symptoms, such as diarrhea, vomiting, cramps and bloating. Only food allergies can result in the life-threatening reaction called anaphylaxis. Symptoms of anaphylaxis include airway swelling, shortness of breath, lightheadedness and low blood pressure. If you don’t treat it quickly, anaphylaxis can lead to death. 

Not everyone with food allergies will have serious reactions, but the possibility will always be there. Your doctor may want you to always keep medicine on hand that can prevent or immediately treat a serious allergic reaction, such as antihistamines and epinephrine (via an Epi pen). 

Allergic to a Single Ingredient in a Dish? Just Say No 
Even if your food allergy reactions have been mild so far, you can’t take a chance that your next one will be. The way your body responds to a food allergy can change from one exposure to the next. “Just one bite” can quickly lead to a ride in an ambulance. Each year, some 200,000 people in the U.S. needed emergency medical care for allergic reactions to food. 

By contrast, when you have a food intolerance, it’s not dangerous to have small amounts of the offending food. Sure, it may make your belly roil in a few hours. But there’s also the possibility that you can enjoy a few spoons of ice cream or a slice of cheese on a hamburger without any symptoms. 

Other Food Reactions 
Not all food reactions become solved mysteries. Consider yourself lucky if you get a firm diagnosis of a food allergy or lactose intolerance. With the former, at least you know which foods to avoid. With the latter, you can still enjoy dairy as long as you opt for lactose-free choices or take a lactase supplement. 

Even celiac disease – which is sometimes described as a gluten intolerance – can be definitively diagnosed. Celiac is autoimmune disease in which your body cannot tolerate any amount of gluten; living with celiac disease means total avoidance of this protein, which is found in wheat, barley, and rye. 

But what if you feel sick after eating other foods? Unfortunately, there are few reliable tests for most food intolerances, and direct-to-consumer “food sensitivity” tests are rife with inaccuracies. 

The silver lining is that your MDVIP-affiliated doctor has the time to work with you and may be able help you get to the bottom of your discomfort, even if it takes many months.