In Wales, older people who are healthier and have more money or education are more likely to get the shingles shot, while those who are sicker or live in care homes are less likely to get it—so whether someone gets the vaccine might just show how healthy and proactive they are about their health.

People in Wales aged 70 and older who got the shingles shot were 28% less likely to be diagnosed with dementia over the next six years — but that doesn’t mean the vaccine prevents dementia, just that the two seem to be linked in some way.

Older people who got the shingles shot seem to be less likely to develop dementia than those who got the flu shot or the whooping cough/tetanus/diphtheria shot — and that’s probably because the shingles vaccine itself is doing something special, not just because getting any vaccine is good for you.

People who have unhealthy lifestyle habits may experience a stronger reduction in cardiovascular risk after receiving the shingles vaccine compared to those with healthier habits.

Getting the shingles vaccine doesn’t seem to make older adults more likely to die or get sudden painful conditions, which suggests that if the vaccine is linked to dementia, it’s probably not because it’s causing general harm.

Getting the shingles shot might help lower your risk of dementia—even if you still get shingles afterward—suggesting the vaccine protects your brain in ways beyond just preventing the rash.