Recently, Robert F. Kennedy Jr., the Secretary of the Department of Health and Human Services, said, “You wonder why a whole generation of children is allergic to stuff. It’s because we’re inducing allergies, pumping them full of aluminum.” RFK Jr. has now asked for the Advisory Committee on Immunization Practices (ACIP) to investigate the safety of aluminum adjuvants in vaccines.
Aluminum adjuvants, which have been used in vaccines since the 1920s, enhance immune responses. Seven vaccines contain aluminum salts as adjuvants: DTaP, pneumococcal, meningococcal, hepatitis A, hepatitis B, Haemophilus influenzae type b, and HPV. None of these vaccines would work well without these adjuvants.
The journal article to which RFK Jr. refers when he claims that aluminum salts in vaccines cause allergies was published by researchers from the Centers for Disease Control and Prevention (CDC) several years ago (Daley M, et al. Association between aluminum exposure from vaccines before age 24 months and persistent asthma at age 24 to 59 months. Acad Pediatr. 2023 Jan-Feb;23(1):37-46). Researchers performed a retrospective analysis of 326,991 children using data from the Vaccine Safety Datalink comparing the quantity of aluminum received in vaccines with the incidence of eczema and asthma. For children with and without eczema, the amount of aluminum received was 4.07 mg and 3.98 mg, respectively. Among children with or without eczema, vaccine-associated aluminum was positively associated with persistent asthma.
The authors offered an important caveat in their discussion section, writing, “While recognizing the small effect sizes identified and the potential for residual confounding, additional investigation of this hypothesis appears warranted.” In other words, these authors understood that they might have failed to account for the effect of extraneous variables. For example, when the authors restricted their analysis only to children who had been fully immunized, the effect of aluminum exposure on the development of asthma was no longer significant. Also, when the authors restricted their analysis to only children who were breastfed, aluminum exposure was not associated with asthma. In addition, the authors could not demonstrate a dose response for aluminum in the risk for developing asthma in the eczema or non-eczema groups. Finally, the authors did not account for exposure to other sources of aluminum in formula or food. All these failures severely limited the conclusions of the study.
Fortunately, other investigators have taken up the CDC researchers challenge to do further studies. Researchers in Denmark examined more than 1.2 million children for 23 years and found no association between the quantity of aluminum received in vaccines and the development of asthma (Andersson NW, et al. Aluminum-adsorbed vaccines and chronic diseases in childhood: A Nationwide Cohort Study. Ann Intern Med. 2025 Oct;178(10):1369-1377).
Recently, Robert F. Kennedy Jr., the Secretary of the Department of Health and Human Services, said, “You wonder why a whole generation of children is allergic to stuff. It’s because we’re inducing allergies, pumping them full of aluminum.” RFK Jr. has now asked for the Advisory Committee on Immunization Practices (ACIP) to investigate the safety of aluminum adjuvants in vaccines.
Aluminum adjuvants, which have been used in vaccines since the 1920s, enhance immune responses. Seven vaccines contain aluminum salts as adjuvants: DTaP, pneumococcal, meningococcal, hepatitis A, hepatitis B, Haemophilus influenzae type b, and HPV. None of these vaccines would work well without these adjuvants.
The journal article to which RFK Jr. refers when he claims that aluminum salts in vaccines cause allergies was published by researchers from the Centers for Disease Control and Prevention (CDC) several years ago (Daley M, et al. Association between aluminum exposure from vaccines before age 24 months and persistent asthma at age 24 to 59 months. Acad Pediatr. 2023 Jan-Feb;23(1):37-46). Researchers performed a retrospective analysis of 326,991 children using data from the Vaccine Safety Datalink comparing the quantity of aluminum received in vaccines with the incidence of eczema and asthma. For children with and without eczema, the amount of aluminum received was 4.07 mg and 3.98 mg, respectively. Among children with or without eczema, vaccine-associated aluminum was positively associated with persistent asthma.
The authors offered an important caveat in their discussion section, writing, “While recognizing the small effect sizes identified and the potential for residual confounding, additional investigation of this hypothesis appears warranted.” In other words, these authors understood that they might have failed to account for the effect of extraneous variables. For example, when the authors restricted their analysis only to children who had been fully immunized, the effect of aluminum exposure on the development of asthma was no longer significant. Also, when the authors restricted their analysis to only children who were breastfed, aluminum exposure was not associated with asthma. In addition, the authors could not demonstrate a dose response for aluminum in the risk for developing asthma in the eczema or non-eczema groups. Finally, the authors did not account for exposure to other sources of aluminum in formula or food. All these failures severely limited the conclusions of the study.
Fortunately, other investigators have taken up the CDC researchers challenge to do further studies. Researchers in Denmark examined more than 1.2 million children for 23 years and found no association between the quantity of aluminum received in vaccines and the development of asthma (Andersson NW, et al. Aluminum-adsorbed vaccines and chronic diseases in childhood: A Nationwide Cohort Study. Ann Intern Med. 2025 Oct;178(10):1369-1377).