Two common vaccines do more than protect against viruses—they reduce the risk of dementia.
In a study involving more than 130,000 older adults in the U.S., researchers found that the shingles vaccine (Shingrix) and the RSV vaccine (Arexyv) were linked to a significantly lower risk of dementia compared to the seasonal flu vaccine.
Specifically, Shingrix was associated with an 18% reduction in dementia risk, while Arexyv showed a 29% drop.
Individuals who received both vaccines saw a 37% reduction—though combining them didn’t produce statistically greater protection than taking just one.
What makes these results especially intriguing is that both vaccines use the AS01 adjuvant, an immune-boosting compound not found in the flu shot. The protection from dementia appeared soon after vaccination, suggesting the benefit may come not from preventing infection but from how the adjuvant affects the immune system. The findings align with a growing theory that dementia could stem from immune system dysfunction in the brain. While more research is needed to understand the mechanism, this study opens the door to using certain vaccines as unexpected allies in the fight against cognitive decline.
source
Taquet, M., Todd, J.A. & Harrison, P.J. Lower risk of dementia with AS01-adjuvanted vaccination against shingles and respiratory syncytial virus infections.