Severe Food Allergies Becoming More Common

That’s roughly six million children. Two in five of the sufferers have a severe allergy that can lead to trouble breathing, a sharp drop in blood pressure and even death.

Dr. Ruchi Gupta, the pediatrician in charge of the study, said doctors, parents and teachers have been warning about the dramatic rise in food allergies, but there has been little research into ways to diagnose or treat them.

How do food allergies form?

	Shellfish such as shrimp are one of the eight foods that account for more than 90 percent of food allergies.

A food allergy results when the immune system incorrectly identifies a harmless food protein as a threat and attacks it. From this point on, whenever the person eats that food, antibodies swing into action and tell the body to create chemicals called histamines. 

Histamines affect cells all over the body, but in particular, the skin, blood cells, lungs and stomach, resulting in allergic symptoms.

Eight foods account for more than 90 percent of food allergies: cow's milk, eggs, peanuts, wheat, soy, fish, tree nuts and shellfish, according to the Centers for Disease Control.

Other foods culprits include apples, carrots, chicken, honey, lettuce, peas, pork, raisins, strawberries and turkey. Many people are also allergic to food dyes, additives and preservatives in processed foods.

Why are rates of food allergies on the rise?

	Dr. Gupta, the lead author of the study, said one theory of why allergies are on the rise is that we have become too clean, and our immune systems no longer get the training they once did.

There are several theories about why allergies areon the rise. Dr. Gupta said one theory is that we have become too clean, and our immune systems no longer get the training they did before the use of antibacterial soap and pasteurized milk became prevalent. 

“Our immune systems aren't able to fight the germs they used to fight, and so they are fighting things they shouldn't be fighting, like food and environment,” she said.

Another theory is that chemicals and pesticides in our foods have altered the healthy bacteria in our gut that help us digest food. 
 
Dr. Gupta said the ongoing National Children's Study, which follows children from before birth until 18, may some day give us an answer.

Anyone can experience food allergies

	Allergic reactions to cow's milk typically begin in childhood but may be outgrown.

Food allergies affect children and adults of all races and ethnicity. According to the Food Allergy Initiative, your risk is higher if you have a parent who suffers from any type of allergic disease.

A food allergy can begin at any age. However, cow’s milk, egg and soy allergies typically begin in childhood and eventually may be outgrown.

A recent study conducted by researchers at Johns Hopkins University School of Medicine indicated that children are taking longer to outgrow milk and egg allergies. Fortunately, the majority are allergy-free by age 16.

Nut, fish and shellfish allergies tend to be life-long.

Recognizing the symptoms

	An EpiPen—a syringe with a single dose of epinephrine that is injected into the thigh—can counteract anaphylaxis,

When histamines reach the skin, stomach, throat,lungs, and in the most serious cases, the heart and cardiovascular system, reactions range from mild to a life-threatening condition known as anaphylaxis. People with anaphylaxis suffer swelling in their lips, tongue and throat.  They have trouble breathing and may turn blue or pass out.

Mild symptoms include hives, eczema, itchy mouth, nausea or vomiting, diarrhea, abdominal pain and nasal congestion or a runny nose.

The chemical adrenaline, also called epinephrine, can counteract anaphylaxis and people with a history of severe reaction often carry an EpiPen—a syringe with a single dose of epinephrine that is injected into the thigh if a reaction occurs.

Those at highest risk for fatal reactions appear to be teenagers or young adults who have both asthma and a food allergy and who do not receive epinephrine in time.