What are Hidden Food Allergies?

Hidden food allergies are negative reactions to foods, beverages, food additives or compounds found in foods. These differ from true food allergies, however, because they do not create immunoglobulin E (IgE) antibodies against the food. A hidden food allergy is also known as food intolerance or non-allergic food hypersensitivity. Food intolerance is a digestive system response rather than an immune system response.

Symptoms of hidden food allergies include headaches, nausea, vomiting, stomach pain, heartburn, diarrhea, irritability and nervousness. Food intolerance, however, might not always result in symptoms if an individual does not eat a large portion of the offending food or eat the food frequently. Food allergies are not the same as food poisoning, which results from spoiled or tainted food.

There are many health problems that arise from hidden food allergies. In just the United States, more than 30 million people suffer from irritable bowel syndrome, which is believed to be caused by unknown allergens. More than 10 percent of Americans suffer from lactose intolerance. Ulcerative colitis, an ongoing disease of the colon, also is very common.

Crohn's disease is often caused by hidden food allergies to wheat, corn, dairy and eggs. Rheumatoid arthritis can be aggravated by allergies to many foods, such as wheat, eggs, sugar, citrus fruits, salt and caffeine. Eczema can be caused by eating wheat, milk, eggs, peanuts and soy protein. A gluten intolerance is known as celiac disease.

Food intolerance happens for several different reasons. Some foods create pharmacological effects, making the body believe that it has ingested a drug. Other foods might contain natural toxins that cause adverse effects in some people. Psychological reactions also can occur if a particular food triggers memories from an individual's past.

The human body has a tendency to crave those foods that cause an allergic reaction. This happens because histamines in the digestive tract are released to fight off the allergen. Histamines provide a pleasant effect on the body, so a person will start to unconsciously want any food that produces them.

Diagnosing hidden food allergies is usually not easy and takes a lot of trial and error. If a food intolerance is suspected, an individual should keep a food diary to record everything he or she eats and the specific times that adverse reactions occur. A pattern of physical symptoms should start to be seen over time. If a person is concerned that certain foods could be bothering him or her, it is best to eliminate the foods to see whether the symptoms stop. These suspect foods can then be reintroduced one at a time to see whether the symptoms return, which would identify a cause of the symptoms.