Close to 8 percent of all children in the United States have a food allergy, according to a comprehensive study published online today by the journal Pediatrics. That’s 5.9 million children.

Until now, the estimates had been anywhere from 1 to 10 percent. “The Prevalence, Severity and Distribution of Childhood Food Allergy in the United States” used data from almost 40,000 children. It found that the most common allergic reactions were to peanuts, milk and shellfish and that nearly a third of those with allergies reported reactions from multiple sources.

The most disturbing figure reported is that 39 percent of children afflicted with food allergies have suffered severe reactions. The researchers wrote that “food allergy can have a profound social and psychological effect on the daily lives of affected children and their families.”

Yes, it can.

Parents who don’t have to endure this problem sometimes roll their eyes at the no-peanut rules or ask, with a detectable scorn, “Why do so many kids have allergies now?”

Today’s study does not approach the “why” question, which is being studied elsewhere. (The New Yorker published an illuminating piece on the subject this year.)

Instead, this report tells us that a significant number of families are struggling with a real and scary condition.

Gina Clowes, founder of Allergy Moms, a national support group, summed it up in an e-mail to me:

“When I work with parents, they typically share that the hardest part is the emotional toll.

“First, there’s the disbelief, and sometimes there is outright hostility. Some people just don’t believe food allergies are real. These issues often escalate at school when accommodations need to be made to keep allergic children safe. Other classroom parents accuse us of trying to control the environment.

“If they only knew. We only want to keep our children safe. I’ll give up baking cupcakes for the rest of my life if my son outgrows his food allergies.”

AllergyMoms produced this moving video on the subject. Given today’s news, it’s worth watching, whether or not allergies are part of your family.

Does your family endure allergies? How do you explain it to other adults?