Young child with bandaid on armDoctors are urging caution on a recent study that suggested a possible link between aluminum in vaccines and persistent childhood asthma. The study had some key limitations that did not consider the full picture of asthma. And it ultimately did not prove the link, although study authors say further research was warranted.

Importantly, “the findings do not provide strong evidence for questioning the safety of aluminum in vaccines,” study authors write.

The U.S. Centers for Disease Control and Prevention (CDC), which funded the study, continues to recommend children receive their routine vaccinations. Vaccines are critical in preventing deadly diseases. If you have concerns, talk with your child’s doctor.

What were the findings of the CDC vaccine study?

CDC funded the study in part to address vaccine safety concerns from many parents. The findings were published in the medical journal Academic Pediatrics.

The study involved 326,991 children born between 2008 and 2014. The children were between 1 month and 2 years of age when they took part in the research. They were recruited from a group of children who received care at clinics taking part in the Vaccine Safety Datalink.

The group was broken up into children who had eczema and didn’t have eczema. (Eczema early in life is a predictor for asthma in about 50% of children as part of the allergic march.) The study then examined:

  • whether the children received vaccines that contained aluminum; and
  • whether they had persistent asthma before age 5.

The average amount of vaccine-related aluminum exposure was 4.07 mg in children with eczema. It was 3.98 mg in children without eczema.

Researchers found that:

  • 6.0% of children with eczema developed persistent asthma
  • In children without eczema, 2.1% developed persistent asthma

The study authors point out key limitations to the research. The results come from a single observational study. The hypothesis that aluminum from vaccines could cause asthma is “speculative.” And it has not been studied in humans.

Researchers also did not take into account other asthma risk factors:

  • family history of asthma, a significant factor in children who develop asthma
  • exposure to secondhand smoke
  • aluminum in the child’s diet (an average of 10 mg per day – more than twice the amount of aluminum in a vaccine)
  • aluminum in the child’s environment
  • social determinants of health

Since these risk factors were not taken into account, doctors could not confirm the link between aluminum in vaccines and persistent asthma in childhood.

Parents and caregivers should continue to follow the childhood immunization schedule. It’s the best way to protect children against serious diseases.

Why is aluminum used in vaccines?

A small amount of aluminum is used in certain childhood vaccines. This is called an adjuvant. It helps increase the body’s immune response to the vaccine, allowing it to work better. The amount of aluminum varies depending on the vaccine, but all are small.

Aluminum is used because it helps provide strong immune protection. It also reduces the number of shots needed in a vaccination series. Aluminum has been used in vaccines for decades.

Vaccines that contain aluminum include:

  • diphtheria, tetanus and pertussis (DTaP)
  • hepatitis A
  • hepatitis B
  • pneumonia vaccines

Aluminum is NOT used in the COVID-19, flu or measles-mumps-rubella vaccines. These vaccines do not require an immune boost that aluminum provides to patients.

You can find aluminum everywhere in our environment, including air, water and soil. Humans consume an average of 10 mg of aluminum per day. Foods are a primary source of aluminum. It is in infant formula, breast milk, fruits, vegetables, dairy, cereal and nuts. For adults, it’s in beer and wine.

The bottom line is there is a lot more aluminum in your environment than you would get in a vaccine. Vaccines are effective at saving lives and preventing significant disease from what can be avoidable infections.


Jacqueline Eghrari-Sabet, MD, FACAAI, is board-certified in allergy, immunology and pediatrics. She served as the Medical Director of Telehealth for Allergy & Asthma Network. Dr. Eghrari-Sabet is the founder of Family Allergy & Asthma Care and the FAAR Institute in the Washington, DC area, where she has been in private practice since 1994. Dr. Eghrari-Sabet is Assistant Clinical Professor at George Washington University School of Medicine and Health Sciences where she mentors the next generation of doctors. She is also President of White Coat Resources, a health education consulting service.