Does the herpes zoster vaccine reduce dementia risk?

The evidence we’ve reviewed leans toward a possible association between receiving the shingles vaccine and a reduced likelihood of being diagnosed with dementia, particularly among women. However, this finding comes from a single assertion, and we do not know if the vaccine itself caused the change, or if other factors—like overall health habits, access to care, or underlying immune differences—played a role. We also cannot say whether this effect would appear in all populations or over longer time periods.

The shingles vaccine is designed to prevent the reactivation of the varicella-zoster virus, which causes shingles. Dementia refers to a group of conditions that affect memory, thinking, and daily function. While the observed link is interesting, we cannot determine if the vaccine directly influences brain health or if the connection is indirect.

Our current analysis shows a pattern worth exploring further, but it is based on limited data. More research would be needed to understand how, or even if, the vaccine might relate to cognitive outcomes over time.

If you’re considering the shingles vaccine, it’s primarily recommended to prevent shingles and its complications. Any potential benefit for brain health remains uncertain and should not be the main reason for getting vaccinated.