Beat that bloated feeling... with a food intolerance test?

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Do you often feel bloated or suffer from indigestion? Do you watch what you eat, but still find it hard to lose those extra pounds? If this sounds like you, then don’t despair – advocates of the food intolerance test will claim that certain foods may be in the way of your weight loss efforts.

The Food Intolerance test has emerged as a method to identify the substances causing symptoms associated with food intolerance such as headaches, chronic pain, and digestive disorders. It also promises weight loss when the detected intolerances were eliminated from the diet. This test seems like a dream come true to many, but is it really?

The test

A finger prick test is used to identify specific immune-based food intolerances. In other words it measures the antibodies, called immunoglobulin, often released by the body’s immune system. Supporters of the test claim that an increase in IgG to a certain food indicates intolerance to that food.

A couple of weeks post testing, a printed list of food intolerances is sent. A friend of mine’s IgG intolerance test yielded the following list: Beef, chicken, salmon, peanuts, eggs, black pepper, olives, carrots, spinach, wheat, corn, lettuce (Lettuce? Seriously?) and her list went on.

So if my friend were to eliminate that long list of food, regardless if she really is intolerant to them, wouldn't it stand to reason that she would lose weight anyway?

Too good to be true?

Although this test seems very appealing, promising to unlock your secret food intolerances, can a simple blood test actually identify and eliminate food intolerance? And what do studies have to say about this tool regarding its sensitivity and reliability?

To date there is no convincing evidence to support this test. This is verified by a recent document released by the Advertising Standards Authority (UK) reporting that following complaints relating to advertising statements, the manufacturers of the IgG food test had to withdraw 13 claims for efficacy and predictability of the test from their website.

Although IgG does play a role in the allergic response, there is no evidence to suggest that it has a diagnostic value in predicting food intolerances that may be affecting individuals. In fact, according to researchers, the level of immunoglobulin reflects the intake of food in the individual and is a harmless finding.

The right test

Food intolerance can have a great impact on the lives of sufferers. An elimination diet is the only way to detect the presence of food intolerances. It is performed by excluding a suspect food for a period of time and during that time symptoms of intolerances such as bloating, diarrhea, migraines, and skin rash are observed and recorded. If symptoms improve upon elimination, then the suspected food is reintroduced. If symptoms return upon reintroduction, this indicates that there is a problem with that particular food.

Because this elimination diet can be complex, it is best carried out under the supervision of a dietitian.

But what do you eliminate? Knowing the most common food intolerances can guide you on the foods you can consider.

Enzyme deficiency such as a deficiency in the enzyme lactase, won’t allow you to digest the milk sugar lactose, thus rendering you lactose, and milk, intolerant.

Histamine, a naturally occurring chemical in certain foods, can cause an allergic reaction in some people. It is often found in process food such as pickled or canned foods, matured cheeses, smoked meat products and vinegar.

Irritants like caffeine, spices, garlic, onions, cabbage, dried fruit and sorbitol (found in sugar-free foods such as chewing gum) can irritate your digestive system.

Food toxins that increase under certain conditions, such as food spoilage, may cause an adverse reaction in some people. For example, green sprouting potatoes may cause a stomach ache in intolerant people.

Sulphites, preservatives used most commonly in wine and dried fruit, can also be considered as a suspect and eliminated in the diet.

Remember, that even if you do happen to have food intolerance, no one ever said it would make you gain weight.


Racha Adib is a Beirut-based licensed dietitian who offers nutrition and wellness counseling to individuals and corporations. She graduated from the American University of Beirut with a Bachelor of Science degree in Nutrition and Dietetics followed by a certificate in Essentials of Business. She is a member of the Lebanese Academy for Nutrition and Dietetics and the Lebanese League for Women in Business. She has also been frequently featured in media on MTV's “The Doctors,” LBC's “Mission Fashion,” and Orbit's “Ayoun Beirut” among others, and hosts a weekly radio program on the latest nutrition news and science breakthroughs. She can be found on Twitter: @rachaadib