Here's food for thought about allergies

food allergyIf some foods leave you feeling itchy and scratchy, queasy or sneezy, you're not alone. Millions of adults and children suffer from food allergies or intolerances.

The most common allergens affecting children are milk, eggs, peanuts, wheat, soy and tree nuts such as walnuts and pecans. In adults, the most common are peanuts, tree nuts, fish and shellfish. Allergic reactions, such as hives, swelling of the throat and shortness of breath, result when the body's immune system sees food as an invader and produces an antibody against it. Children are more susceptible because their digestive systems are undeveloped and their immune systems are more often exposed to food proteins, says Andy Nish, an allergist. The exposure decreases as their bodies mature.

Children tend to outgrow allergies to milk, egg and soy, but once you develop a true food allergy as an adult, you are unlikely to outgrow it, Nish says. In addition, an allergy to peanuts and tree nuts is seldom outgrown, he says.

If you eat something that causes stomach discomfort, cramping and diarrhea, it doesn't necessarily mean you're allergic to it. Other illnesses, such as the flu, produce similar symptoms .

"Up to one in four adults changes their diet for perceived problems that are not a problem," says Scott Sicherer, an associate professor of pediatrics at Mount Sinai School of Medicine in New York.

Here are a few steps to determine if you have an allergy or food intolerance:

Keep a food diary for one or two weeks detailing what and when you ate, any negative reactions you had and how long they lasted, Sicherer said. If your reactions occur away from home, write down the list of ingredients from the restaurant or product label.

If the reaction isn't extreme, remove suspected foods from your diet one at a time until symptoms disappear and reintroduce one at a time to see if reaction recurs.

Visit your primary doctor to rule out other probable causes, such as a virus. If necessary, get referred to an allergist who can run a skin or blood test to detect antibodies.

If an allergy is identified, the best treatment is avoidance. There are no immunizations or treatments to prevent food allergies. People known to have extreme reactions might need to carry epinephrine in case of life-threatening attacks.

Food intolerances, however, can often be managed by treating symptoms with over-the-counter medications.