Jennifer Holub boycotted all things peanuts after her two year old son Henry had an allergic reaction to a peanut butter sandwich.

“He broke out in full body hives,” she said.

Even though her other two sons haven’t shown signs of peanut allergies, Holub isn’t taking any chances.

“It’s especially frustrating with the other two boys who don't have the allergy or we're not sure if they have the allergy,” she said.

Henry’s doctor, Dan DeMerell with Legacy Emmanuel Children’s Hospital, says when in doubt, it’s best to go without.

“The treatment unfortunately at this point is avoidance,” said Dr. DeMerell.

The symptoms can include nausea, cramping, vomiting and diarrhea. The most common food allergies in children are cow’s milk, eggs, wheat, peanuts and soy.

Doctors don’t know what causes the food allergies but there are a couple of theories. One is the Hygiene Hypothesis, meaning we’ve become too clean.

“We’re living in more sterile conditions, more vaccines, more antibiotics not playing in the dirt so much as in the past,” said Dr. DeMerell. Another theory is the way foods are processed like dry roasting peanuts could make foods more allergenic.

Two years ago, the federal government began requiring food manufacturers to have better labeling. While Holub scrutinizes the labels she knows she can’t fully protect her son.

“I think right now the worry is the difficult part the worry what if he has an accidental exposure to it what if he does go into shock next time?,” she said.