Shingles and Pneumonia Vaccines Linked to Lower Dementia Risk, New Research Suggests
November 9, 2025 – Emerging research is suggesting a surprising connection between common vaccinations – those for shingles and pneumonia - and a reduced risk of dementia. A new study, published recently, adds to a growing body of evidence that these vaccines may offer a protective effect against the debilitating neurological condition.
The study,analyzing the health records of over 400,000 adults in the United States,found that individuals who had received either the shingles or pneumonia vaccine had a considerably lower risk of being diagnosed with dementia in the years following vaccination. Specifically, the shingles vaccine was associated with a 26% reduction in dementia risk, while the pneumonia vaccine showed a 13% reduction.
“This is compelling enough that physicians may begin discussing dementia prevention as an added benefit with their patients,” said Dr. Michael jena,the Joseph P. Newhouse Professor of Health Policy at Harvard Medical School. He noted he recently introduced the connection to a group of residents who were previously unaware of the potential link.
The findings build upon previous research, including a 2017 study co-authored by Dr. Geldsetzer, which examined over 280,000 adults in Wales and found a 20 percent lower risk of dementia in those who received the shingles vaccine over a seven-year period.
Researchers found the protective benefits appeared to correlate with the duration of vaccine effectiveness. As the vaccines’ protection against their target illnesses waned, so too did the observed benefits regarding dementia risk.
While the exact mechanism behind this connection remains unclear, experts theorize that the vaccines may stimulate the immune system in a way that benefits brain health.
“Current options for reducing the risk of dementia are limited and not as effective,” explained Dr. AM Barrett, chair and professor of neurology at UMass Chan Medical school and chief of neurology at the VA Central Western Massachusetts Healthcare System. she cautioned, however, that the issue could become politicized, possibly fueling mistrust in medicine and vaccinations.
“Unfortunately,” Dr. Barrett said, “people who are not personally affected by dementia may see this as an attempt to persuade them to receive an unnecessary vaccination.” Despite this concern, she emphasized the value of the potential benefit. “You want to be able to play with your grandchildren for five more years and be able to drive well for another five years,” she said. “This is priceless.”
The study underscores the importance of staying up-to-date on recommended vaccinations,not only for preventing infectious diseases but potentially for safeguarding long-term cognitive health.
About the Author:
Akilah Johnson is a national reporter who investigates the impact of racism and social inequality on health for The Washington Post. She joined the Post in 2021 after working at ProPublica, where she won a George Polk Award and a national Magazine Award and was nominated for the Pulitzer Prize for her investigation into the impact of Covid-19 on Black Americans.
(This article was first published in English on November 9,2025 at Washingtonpost.com and is now available in translation to readers of the IPPEN.MEDIA portals.)
