Health and Human Services Secretary Robert F. Kennedy Jr. recently suggested that aluminum in childhood vaccines could be a factor in the development of peanut allergies. Experts say his claim lacks credible scientific support and risks discouraging parents from vaccinating their children.
What Kennedy said
At a Food Allergy Fund leadership forum, Kennedy questioned the prevailing idea that a lack of early peanut exposure explains rising peanut allergy rates and suggested instead that the timing of aluminum’s use in vaccines might be linked to the increase. He also said his agency plans to research food allergies and their causes.
What scientists and clinicians say
Pediatricians, allergists, and vaccinologists say there is no convincing evidence that aluminum in vaccines causes peanut or other food allergies. Danelle Fisher, MD, a pediatrician, noted that people ingest and inhale far more aluminum in daily life than they receive from vaccines. Inderpal Randhawa, MD, an allergist and CEO of the Food Allergy Institute, pointed out that aluminum has been used in most pediatric and adult vaccines for more than eight decades; if aluminum caused food allergies, rates would have been rising continuously for far longer.
Anne Liu, MD, a pediatric clinical professor at Stanford, said large studies have found no credible association between vaccination and increased allergy risk.
Aluminum in vaccines and everyday exposure
Aluminum has been used as a vaccine adjuvant since about 1926. Adjuvants boost the immune response so smaller amounts of antigen and fewer doses can be used. Aluminum is also the third most abundant element in Earth’s crust and appears in food, water, soil, and many consumer products.
An infant receives just over 4 mg of aluminum from vaccines in the first six months of life; breast milk and formula contain trace amounts as well. A large Danish study of 1.2 million children born 1997–2018 found no link between aluminum exposure from vaccines in the first two years and increased rates of any of 50 studied disorders, including food allergies.
Trends in peanut and food allergies
About 33 million people in the U.S. have a food allergy — roughly 1 in 10 adults and 1 in 13 children. Peanut allergy affects an estimated ~2% of U.S. children, and while rates rose notably around the turn of the century (a 2010 report found rates had tripled between 1997 and 2008), guidance on infant feeding has changed in response to research.
Earlier advice to delay potentially allergenic foods was overturned after the 2015 LEAP trial showed that introducing peanut-containing foods before age 1 significantly reduced peanut allergy risk by age 5. From about 2017, medical organizations began recommending gradual early introduction of peanuts for many infants. An October study reported a decline in childhood peanut allergy rates after these guidelines — from 0.92% before to 0.67% afterward, a roughly 27% reduction.
Causes of peanut allergy are complex
Researchers do not know a single cause for peanut allergy. Factors implicated include genetics, family history, other atopic conditions (like eczema), environmental exposures such as pollen, immune system development, and possible roles for vitamin D and other variables. Experts emphasize allergy development is multifactorial rather than traceable to a single cause like aluminum in vaccines.
Why accurate messaging matters
Clinicians warn that linking vaccines to allergies without solid evidence could reduce vaccination rates. Vaccines prevent serious, sometimes fatal diseases (measles, whooping cough, etc.), and falling coverage undermines community protection, endangering infants, pregnant people, the elderly, and immunocompromised individuals.
Bottom line
Current evidence does not support a causal link between aluminum in vaccines and peanut or other food allergies. Aluminum has long been used as an adjuvant and is ubiquitous in the environment; large studies have not found associations between vaccine aluminum exposure and increased allergy rates. Early introduction of peanut-containing foods, guided by current medical recommendations, has been associated with reductions in peanut allergy prevalence.
