In 2000 and the decade following, pediatricians recommended delaying the introduction of peanuts in babies and children until the age of three years to reduce this potentially fatal food allergy. Between 1997 and 2008, the rate of peanut allergy in children tripled.
Now, looking at the data, it’s clear that delaying the introduction of peanuts led to the alarming rise in peanut allergy. What followed was landmark research published in 2015 that completely changed how we approach the prevention of food allergies in infants and children.
Researchers were first intrigued by the strikingly low rates of peanut allergy in Israel, where babies commonly eat a popular peanut-based snack called Bamba soon after they begin solid foods. In contrast, peanut allergy was far more common in Western countries where parents were told to delay introducing peanuts.
The LEAP study (Learning Early About Peanut Allergy) led by Dr. Gideon Lack and his team at King’s College London studied more than 600 infants at high risk of peanut allergy with severe eczema, egg allergy or both. Infants were randomly assigned to either avoid or consume peanuts until the age of five. The results were dramatic. Those who ate peanuts early and sustained intake had a substantial and significant decrease in the likelihood of developing a peanut allergy.
Introducing peanuts before a baby’s first birthday can dramatically cut the risk of peanut allergy by age five. In fact, high-risk infants who regularly ate peanut foods were up to 86 percent less likely to develop an allergy than those who avoided them, showing that early exposure helps the immune system build tolerance rather than fear peanuts.
This emerging science led the American Academy of Pediatrics, the National Institute of Allergy and Infectious Diseases and others to update their guidelines, and by 2017, caregivers and parents were being advised, under medical supervision, to introduce peanut-containing foods to at-risk infants as early as four to six months old. For most babies, early peanut introduction is now seen as both safe and beneficial.
These findings were nothing short of a paradigm shift. While allergen avoidance was thought to be protective, LEAP proved that early, controlled exposure helps train the immune system to tolerate peanuts rather than react to them. This concept, known as oral tolerance, has since become the foundation of modern allergy prevention.
The results of this policy reversal have been extraordinary. Researchers estimate that in the United States alone, tens of thousands of peanut allergies have been prevented over the past decade. Modeling studies suggest that if all families followed the updated guidance, the number of new peanut allergies could be cut by up to 80 percent. This represents one of the most successful public health interventions in recent history, achieved not through medication, but through food. Thanks to this shift, countless children who might have grown up with life-threatening peanut allergies can now safely enjoy one of childhood’s favorite foods.
For parents, this shift can be both empowering and reassuring. The once-daunting task of avoiding peanuts has been replaced with a proactive, evidence-based approach for prevention. Simple measures like mixing a small amount of smooth peanut butter with puréed fruit or yogurt can help a child’s immune system build tolerance early on.
Note: It is generally advised to consult with your healthcare provider before introducing peanuts to infants, especially those at high risk due to severe eczema or egg allergy, to determine if allergy testing or supervised introduction is recommended. Keep in mind, also, it is important to ensure proper, choking-hazard-free introduction.
LeeAnn Weintraub, MPH, RD is a registered dietitian, providing nutrition counseling and consulting to individuals, families and organizations. She can be reached by email at RD@halfacup.com.