A rising number of U.S. children are allergic to peanuts, and doctors still aren't sure why.

But experts are increasingly convinced that feeding peanut-containing foods to infants can lower their chances of developing an allergy later in life.

To that end, a national panel of allergy specialists has created the first-ever guidelines that show parents and health care providers how and when to introduce all infants to peanuts.

The guidelines continue the broader shift away from earlier advice that parents shouldn't introduce babies to peanuts before their first birthdays.

Researchers say their goal is to shield future generations of children from dangerous food allergies.

"You can take a major health issue off the table before it even starts," said Matthew Greenhawt, who chairs the food allergy committee of the American College of Allergy, Asthma and Immunology (ACAAI).

"We're hoping to decrease as many cases of peanut allergy as possible -- ideally in tens of thousands of children," he told Mashable.

Greenhawt co-authored the new guidelines as a member of the 26-person panel, which was sponsored by the National Institute of Allergy and Infections Diseases, part of the National Institutes of Health.

The guidelines, published Thursday in the Journal of Allergy and Clinical Immunology, suggest that parents can introduce infants to peanut-containing products around the age of 6 months.

Certain restrictions apply to high-risk babies who have eczema or egg allergy, and all parents should discuss the guidelines first with their child's pediatrician before taking action.

Experts also stress that they don't mean giving whole peanuts to infants -- that's a choking hazard. Peanut-containing foods might mean watered-down peanut butter or purees containing peanut.

Peanut allergy is a growing public health problem in the U.S. and other countries, yet it still lacks any treatment or cure.

Common allergic reactions to peanuts include hives, rashes and itchy skin. In more severe cases, people can have a life-threatening reaction that hinders their breathing and sends their body into shock.

About 2 percent of U.S. children -- or 1 in 50 kids -- is allergic to peanuts, according to a 2011 national survey. That's up from just 0.4 percent of children in 1999.

Greenhawt said allergy and pediatric experts still don't know why peanut allergies are becoming more prevalent, although researchers are studying whether it has to do with children's lack of early exposure to peanuts, low levels of Vitamin D in kids or our immune system's bizarre reaction to the decline in infectious diseases.

The first hypothesis -- that a lack of peanut exposure results in allergy -- has gained the most traction, especially in light of a landmark 2015 study.

The clinical trial involved hundreds of babies in London, where children typically don't consume any peanut-containing foods early in life, and in Tel Aviv, Israel, where babies often eat peanut-containing foods before they can walk.

Researchers found that babies who ate the equivalent of 4 heaping teaspoons of peanut butter every week -- starting when they were between 4 and 11 months old -- were about 80 percent less likely to develop an allergy by age 5.

"It seems that the earlier you give the [peanut-containing] food, there's a window where the immune system just doesn't see it as dangerous," said Greenhawt. "The body can be educated in a different way and tolerate the food."

The 2015 study prompted U.S. allergy and pediatric experts to develop the new guidelines.

They are, in brief:

• For low-risk children (with no eczema or egg allergy): Once infants can eat solid foods, introduce them to peanut-containing foods at around 6 months.

• For moderate-risk children (with mild-to-moderate eczema): Parents can introduce infants to peanut-containing foods at home, starting at around 6 months.

• For high-risk infants (with severe, persistent eczema and/or egg allergy):Introduce peanut-containing foods as early as 4 to 6 months. Parents should first check with their infant's health care provider, who may choose to do an allergy blood test or send the infant to see a specialist. The results of these tests will help decide if and how peanuts should be introduced into the infant's diet.

Last year, the American Academy of Pediatrics endorsed similar recommendations to give high-risk infants peanut-containing foods around ages 4 to 11 months. Major allergy groups from Canada, Europe, Japan and beyond have also backed this approach.

Thursday's guidelines are the first to encourage parents to take a proactive steps for all infants.

"We're actively saying, 'Do this, and it's associated with a risk-reduction benefit,'" Greenhawt said.

"It's a much stronger and more targeted recommendation."