Fiber Allergy

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When you think of an allergy, fiber probably doesn’t come to mind. That’s because a fiber allergy is not an accurate diagnosis. If you experience adverse reactions when you eat fiber, you may be eating too much fiber, have a wheat allergy or an intolerance towards certain grains. Many people confuse an allergy with another condition because the digestive symptoms are similar. Only your doctor can determine which condition is causing symptoms. Do not attempt to self-diagnose based on symptoms alone.

Fiber Consumption

Fiber is an essential substance needed for proper digestion and overall health, according to Fiber assists your digestive tract in keeping food moving throughout the intestines and maintaining regularity. Lack of adequate fiber in your diet can lead to constipation and other health concerns. Most Americans don’t eat the recommended daily fiber intake of 25 g to 35 g. If you begin eating high fiber foods or take fiber supplements abruptly, you can experience bloating, gas, nausea, diarrhea and vomiting. These symptoms may be confused with an allergy.

Wheat Allergy

You may be confusing fiber consumption with eating wheat. If you’re allergic to wheat, you may also be allergic to oats, rye and barley because they all contain a similar protein, gluten. According to, someone with a wheat allergy has a hypersensitivity to one of four main proteins found in wheat. When you consume wheat products your immune system reacts as if it’s under attack and begins producing immunoglobulin E, or IgE antibodies. The creation of these antibodies leads to a chemical chain reaction in the body and causes common allergy symptoms, such as skin rashes, asthma, nasal congestion and digestive issues, according to the American Academy of Allergy, Asthma and Immunology.


A food intolerance and allergy are two different conditions that are commonly confused. Food intolerance is considered more common than an allergy and is typically associated with grains, dairy and certain sugars. The American College of Gastroenterology states that food intolerance is an inability of the digestive tract to properly break down certain proteins and sugars in various foods. The symptoms of an intolerance will only affect the digestive system; bloating, gas, vomiting, nausea, diarrhea, abdominal pain and cramping.


If you develop diarrhea as a result of eating fiber, talk with your doctor. Diarrhea can cause dehydration, a serious medical condition that can be life-threatening. Your doctor may recommend that you modify your diet to alleviate the symptoms.