Food intolerance tests

If mealtime leads to digestive discomfort often, then you may be suffering from a food intolerance. Although symptoms of a food intolerance are not as serious as a food allergy, they can still reduce quality of life. Therefore, it may be helpful to find out if you have a food intolerance so you can make mealtime more enjoyable. Read below for advice on tests you can have done to find out if you have a food intolerance so you can start making necessary changes in your diet.

What is a food intolerance?

People may often use the terms food allergy and food intolerance interchangeably. However, there are major differences between these two conditions. A food allergy involves an immune system reaction with symptoms like hives, itching, swelling of the tongue or lips, trouble breathing, nausea, or dizziness, to name a few.

On the other hand, symptoms of a food intolerance are primarily of a digestive nature. Such symptoms include:

• Bloating
• Stomachache
• Gas
• Diarrhea

Other symptoms of as food intolerance may include headaches and skin rashes like hives. Symptoms of a food intolerance may present themselves a few hours after ingesting the food, or up to 48 hours after. If you find that you experience such symptoms often, then it may be time to be tested for a food intolerance.

Causes of food intolerances

Before you have tests done, it may be helpful to know what can cause a food intolerance. Several factors can put you at risk for developing a food intolerance that include:

• Absence of an enzyme, such as in cases of lactose intolerance: Those with lactose intolerance lack the enzyme lactase that helps break down the milk sugar lactose. Without this enzyme, when people with lactose intolerance consume milk or milk products, they develop uncomfortable digestive symptoms such as those listed above.
• Food poisoning: Certain foods, such as uncooked beans, contain certain compounds that the body just cannot handle. Also, foods that have gone bad may develop bacteria that can upset the stomach in turn causing food intolerance symptoms.
• Intolerance to histamine: Histamine is a substance found in certain foods, such as pickled or fermented foods, aged cheeses, or smoked meats. Some individuals may be intolerant to histamine, and in turn may experience digestive symptoms like diarrhea, stomach cramps, or bloating when they consume such foods.

How to test for food intolerances

A simple way to determine if you have a food intolerance is to start a food-symptoms diary. This involves writing down everything you eat and drink every day along with symptoms you may feel. It will be important to also write down what time you consume everything and when you feel symptoms.

This way, if you feel any symptoms, you can look back and see what you may have eaten that could have caused symptoms. A registered dietitian who specializes in gut health issues may be able to help you use this method for figuring out what may be causing your symptoms. You can then eliminate such foods from the diet and see if that helps reduce your frequency of symptoms.

Besides a food-symptom diary, other methods of testing for food intolerances include:

• Blood tests such as the Mediator release test (MRT): This type of test uses a blood sample to test the reaction of the white blood cells when exposed to certain food antigens. If the antigen causes a change in the solid to liquid ratio in the white blood cells, then it suggests that they have released chemical mediators like histamine that could provoke symptoms in the body. However, since limited studies have been done on this method, there is no guarantee this method accurately predicts food intolerances.
• Antibody tests: Certain antibody tests like IgG, may be helpful in determining food intolerances. A blood sample is used to test for such antibodies that are produced when the body is exposed to certain food compounds. However, more studies need to be done to confirm the accuracy of this method.
• Elimination diet: This method of elimination is similar to the food-symptom diary method in that it eliminates common foods that may trigger food intolerances and then gradually adds them back in to see if they cause symptoms. Typically, common triggers will be eliminated for at least two weeks before adding foods back in. And during this adding back phase, foods will only be added in one every three days. This allows plenty of time for any potential symptoms from consuming the food to present itself. This type of diet should be done under the supervision of a gut healthcare provider such as a gastroenterologist or gut health dietitian.

Take home message

If you experience uncomfortable digestive symptoms after mealtime often, then it may be time to be tested for a food intolerance. There are many methods of testing for food intolerances, however there is no gold standard. Therefore, it may take a process of elimination of foods in the diet, under the supervision of a healthcare provider like a registered dietitian, to help determine what foods may be causing you discomfort. For more information on gut health issues, be sure to visit the Casa de Sante website.