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You may not suspect that your stuffy nose, upset stomach, fatigue, or irritability might be caused by last night’s dinner or that snack after your morning vinyasa class. But according to some authorities, for about 20 percent of the population, certain foods can cause those symptoms—and more.
“Food allergy involves an abnormal immune response to food following ingestion, while food sensitivities involve an abnormal but nonimmunological response,” explains Randy Horwitz, medical director of the Arizona Center for Integrative Medicine at the University of Arizona in Tucson. In other words, if you have a sensitivity, your body may not like a certain food, but it won’t make you sick.
There are differing opinions about what causes food sensitivities, but some health and nutrition experts blame a genetic predisposition, such as an enzyme deficiency, which makes it difficult for the body to digest certain food components (such as lactose, a sugar in cow‘s milk). Intolerance of eggs or wheat is also common. Some people experience sensitivity to chemical constituents—either natural or synthetic—in certain foods.
Symptoms of food intolerance can include gastrointestinal upset, sinus problems, headaches, fatigue, joint pain or muscle ache, edema (swelling), anxiety, mood swings, and even anemia, says Stephen Wangen, director of the IBS Treatment Center and the Center for Food Allergies, in Seattle.
How do you know if you are sensitive to a certain food? Unlike an allergy, which can be tested for as a reaction to specific antibodies, food intolerances require you to do your own sleuthing. If you suspect that certain foods are making you ill, Horwitz recommends keeping a food diary. This method alone may not pinpoint any one culprit, but it will probably narrow the field. Once you identify a few suspects, remove each from your diet, one at a time, for about a month; then reintroduce it and watch for reactions.
Sometimes the only cure for food sensitivities is to avoid the offending product, at least for a while. Over time you may be able to reintroduce small amounts into your diet.
“Health is a balancing act. The more things you have in your favor, such as mind-body awareness, exercise, healthy diet, and adequate sleep, the better your health will be and the more easily you’ll be able to absorb the occasional negative [food reaction],” Wangen says.
Log It In
Keeping a food diary can help you identify possible food intolerances. For at least two weeks write down:
- everything you eat
- how it was prepared
- when you ate it
- any unusual symptoms that occurred after consumption