Why Are Cases Increasing?

Food allergy rates around the world are skyrocketing. Twenty years ago, perhaps one or two children in an entire school population had a severe allergy; today there are at least ten times as many. What is causing this increase?


Scientists believe many, if not most, food allergies have a genetic basis. That is, if food allergies run in your family, your chances of developing one are increased. If both parents have food allergies, there is a 60 percent chance that at least one of their children will have an allergy. But even if there is no history of food allergies in the family, 5–15 percent of children will develop one.

Too Clean, or Too Dirty

You may have heard warnings about overuse of antibiotics and antibacterial cleansers. Not only do these practices force bacteria and viruses to mutate, but the evolved germs can become resistant to current drugs and medicines. And there's another angle: Children who grow up in a very clean environment don't develop as many antibodies to germs, so their immune systems may be underused or “bored” and will strike out against other substances, such as food. This is called the Hygiene Hypothesis.

Studies have shown that allergies are less common in children who attend day care and early preschool; who grow up in rural areas, especially farms; who have pets; and who have older brothers and sisters who bring germs and illnesses home from school.

Conversely, inner-city children, children of smokers, and children who live in very polluted areas have more allergies and food sensitivities. Rates of asthma are particularly high in the most polluted areas. Therefore, environmental toxins and pollution may play a role in allergy development.

Should I ditch the soap?

Proponents of the Hygiene Hypothesis don't want you to stop washing your hands or cleaning the kitchen. But using plain soap and water instead of antibacterial solutions and soaps may lead to a healthier family. Children who play in the dirt, have pets, and contract normal childhood diseases can be healthier than those who are overly protected.

Moderation May Be Key

The lesson may be to simply avoid the extremes. Don't become obsessed with cleanliness. Let your children play in the dirt and with animals, and don't shy away from everyone who sneezes.

Finally, don't smoke! Smoking is a proven cause of a wide range of maladies, including asthma, SIDS, allergies, bronchitis, and cancer. Secondhand smoke is particularly dangerous for children.

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