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Are You Sure You Have a Food Allergy?

7 min read

By Catherine Roberts

Medically Reviewed by Julie Ching, MS, RDN, CDE

Food allergies are widespread, and if you have children you probably can’t put peanut butter sandwiches in their school lunchbox because of the risk to children with severe peanut allergies. But aside from the most common food allergies that are often quickly and easily diagnosed—like peanuts, tree nuts, milk, and eggs—there are a lot of symptoms that may seem like allergic reactions but aren’t. Instead, they could be caused by a mild to severe medical condition or disease that requires treatment and lifestyle changes to manage. Being properly examined and diagnosed is integral to make the safest diet changes and avoid long-term complications.

Continue reading to learn about diseases and other health problems that mimic allergies—you may recognize your own symptoms that lead you to believe you have a food allergy…

Misdiagnosing Celiac Disease

Celiac disease is an autoimmune disorder that causes inflammation in the small intestine and prevents the body from absorbing certain nutrients. While over the past decade health professionals have more actively begun testing for gluten sensitivities—causing a surge in the amount of people diagnosed with it—many people actually have celiac disease, which may present symptoms like an allergen but is a serious condition not always tested. Celiac disease causes long-term damage to many vital organs if gluten is consumed, so it’s important to speak with your doctor about it if you experience any reaction to the protein.

Short-term, immediate symptoms of celiac disease that mimic those of an allergen include bloating, cramping, and diarrhea. Other symptoms include anemia, weight loss, and fatigue. While the symptoms and severity of reactions to gluten varies widely among those with celiac disease, permanent and serious damage occurs even with mild reactions to gluten. This is why it’s important to be properly diagnosed and to avoid gluten completely for the rest of your life if you have the disease.

Intolerance vs. Allergies

It’s common for people to confuse a food intolerance with a food allergy. It may seem that a lot of people have allergies, but this isn’t necessarily the case. According to the Mayo Clinic, it’s more common for a physical reaction to food to be caused by a food intolerance than a food allergy. Yet there seems to be a pretty big misconception about this. The main difference between an intolerance and allergy is that allergies cause a reaction in your immune system, while an intolerance is your body’s inability to break down or digest specific foods or compounds.

Gluten-intolerance is a good example of something often confused with an allergy because people think the reaction is one of an allergen. You’ve also probably heard someone say their food intolerance is “like an allergy”, something many do just to help others quickly understand. Luckily, the reaction from a food intolerance is typically less severe than that of an allergy. Since many allergies can be life-threatening, some people need to carry an injection that releases epinephrine into the body to lessen the severity of an allergic reaction.

Unknown Ulcers

The cause of ulcers has been historically incorrect among the masses, with symptoms like abdominal pain that lead you to believe you have a food allergy if it happens after eating. You might have heard that stress, alcohol, and spicy foods cause ulcers but they aren’t actually to blame. Yes, your ulcer may get irritated and feel worse after consuming certain foods and when dealing with stress. But the true causes are from a specific bacteria found in the stomach lining, and certain pain relievers and some other medications, all which irritate and cause inflammation in the stomach lining.

According to the Mayo Clinic, it’s common for ulcers to cause nausea, vomiting (both food and blood), blood in the stool, weight loss, and appetite change. Ulcers are open sores in the stomach lining and small intestine, and can be quite painful. They can come and go but are irritated and cause pain when stomach acid comes in contact with the sore. You may try to avoid certain foods and take antacids to help with mild symptoms, but if you’re regularly experiencing pain and over-the-counter medications aren’t working, consult with your doctor.

Undiagnosed Irritable Bowel Syndrome (IBS)

You’ve probably uttered the words “something in that food didn’t agree with my stomach,” or some variation of it. And if it happens often, you might jump to the conclusion that you’re allergic to a certain food or food additive. But you could have irritable bowel syndrome, a condition that usually requires lifelong treatment, diet and lifestyle changes to reduce the severity of symptoms and lower the risk of flare ups. It’s a very treatable condition once confirmed, so it’s important to see your doctor.

Some of the symptoms of IBS that mimic food allergies are abdominal cramping and pain, bloating, and diarrhea. While many people assume they have a food allergy when experiencing these symptoms, there are so many possible causes—some of which can be serious if not caught early enough—and a food allergy isn’t often the problem. It’s also important to note that even if you think it’s an allergy that you can manage on your own, you should still see your doctor about any new symptoms you experience or changes in your stool and bowel movements.

Hiatal Hernia

So many diseases and medical conditions seem like a food allergy, including hiatal hernia, which might seem like heartburn. Because many with the condition assume it’s an allergy or that certain foods cause them heartburn, they don’t get their doctor’s help until the symptoms are too severe and last a long time. It’s quite the surprise then to find out that hiatal hernia is the cause of heartburn and difficulty swallowing, symptoms that you attributed to a food allergy.

With hiatal hernia, your stomach pushes up through the opening between your esophagus and the small opening that leads to your diaphragm. The size of the opening varies depending on the patient, and additional symptoms (beyond heartburn and trouble when swallowing) are fatigue and excessive belching. When all of these symptoms are felt, odds are you’ll go to your doctor who will confirm that you do not have an allergy. The good thing is, small hiatal hernias don’t cause any symptoms, and large ones are usually manageable through medication and lifestyle changes.

Excessive Histamine

Hives. A flushed, puffy face. Redness. These symptoms sound exactly like an allergic reaction, and it’s seemingly obvious you should avoid the food you just ate if you think it caused a reaction. But these symptoms, while common for many allergy sufferers because of the role histamine has during a reaction, may not actually be from a food allergy. Instead, a histamine intolerance may be the culprit. This is when your body has excess histamine, and it can look and feel just like an allergic reaction.

Histamine is a chemical compound stored in cells in your body. It’s released during allergic reactions, which is why excess histamine often isn’t considered as the cause. According to an article in the American Journal of Clinical Nutrition, excess histamine can occur from enzymes in your body not functioning effectively. Then, when you eat foods high in histamine, or take drugs or drink alcohol that release histamine or block enzymes from doing their job, you end up having a reaction.

Sensitivity to Food Additives

In today’s world, your options for prepackaged and preserved foods are endless. The rush and stress of busy lives leads people to look for meals you simply need to heat, and there’s a lot of appeal for snacks you can eat on the run. Simply put, you don’t have to worry about making a home-cooked meal or snack from scratch if you don’t want to. But many people claim these convenient meals and snacks that are packed full of chemicals, preservatives, and fillers, are the cause of allergy-like symptoms.

There’s quite a bit of controversy about what role food additives have in causing reactions. Some people experience swelling, hives, stomach cramps, diarrhea, nausea, and sweating after eating something with a certain additive. For the reactions that have been documented, the severity can range from very mild to extreme. In some cases, it’s claimed the additive can bring on an allergic reaction or induce an asthma attack, depending on the additive. So if you often experience allergy symptoms, try cutting out prepackaged foods you eat regularly to see what happens, and book a visit with your doctor to be safe.

Enzyme Deficiency or Improper Function

Enzymes deficiencies and enzymes that don’t do their job properly can cause symptoms that are commonly confused as a food allergy, and it’s understandable why—the symptoms range depending on the enzyme, but it’s common to experience a combination of things, from bloating and gas to rashes and abdominal discomfort. Enzymes are important because they affect the speed of chemical reactions in the body, or more specifically, they speed the reactions up. If the process doesn’t occur fast enough, your body can be affected in many ways.

With your body dependent on enzymes for thousands of metabolic processes, it’s no surprise you will experience symptoms and potentially develop other medical conditions or problems if they aren’t doing their job. But any symptoms you have directly from an enzyme deficiency are not an allergic reaction to food. Interestingly, food intolerance can be caused by enzyme deficiencies, further connecting the problems in the process to other conditions that mimic a food allergy. Examples of enzyme deficiencies include lactose and fructose intolerance.

Children Disliking Foods

Odds are that you or someone you know who has children have cut something out of their infant or toddler’s diet because of a suspected food allergy. It’s a fairly common decision among parents when their young child gags, vomits, or turns away from eating or drinking something. They may present other symptoms, like diarrhea, making you think they are allergic to a certain food. But what many parents don’t do is check with their doctor first and consider the overall health effects of cutting out a major food group.

Removing an important food group from a young child’s diet can be risky. Why? It’s difficult to ensure the child gets all the nourishment needed to develop and thrive when something major is cut out. And with young children, those under 2 years old, what might seem like a food allergy could actually be a psychological aversion to something or an intolerance, which changes the approach to the situation. So if your child gets sick, whether from a food allergy, intolerance, or even a psychological reaction, it’s safest to find out what to do from an expert—your doctor or nutritionist.


Julie Ching is a Registered Dietitian and Certified Diabetes Educator in Los Angeles. She decided to become a Dietitian after traveling through Europe, South America, and Asia and discovered a passion for food. She now works with people of all ages and varying disease states to improve their health. She is passionate about teaching people about nutrition so they can live their best life while still considering their cultural and socioeconomic backgrounds.

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