Dementia Vaccine Discovered? (Here’s the TRUTH)
It was the moment millions of seniors were waiting for…
Right until it wasn’t.
A new study claimed that a common vaccine – one you may have gotten anyway – could slash your risk of ever developing dementia.
It got international news coverage – and was even pushed out to doctors on medical websites.
But there are a few things about this so-called “dementia vaccine” discovery they don’t want you to know.
It did NOT prove the vaccine prevents dementia.
The results have been wildly inflated.
And every person considering the shot deserves to know the whole truth.
Now, if you read the media headlines, you’d come away thinking that a new study published in The Lancet Neurology found that people who got the shingles vaccine were less likely to develop dementia.
Not true.
The truth is, researchers don’t know whether people vaccinated against shingles went on to develop dementia or not.
Sounds a bit less promising, no?
Back in 2016, the province of Ontario in Canada launched a rollout of the shingles vaccine Zostavax for seniors, making it available for free.
Researchers looked at people who were eligible for the free vaccine program and determined they were less likely to develop dementia over the course of 5.5 years.
Yes, you read that right. They just looked at people who were eligible for the shot… not who actually got it.
This was similar to a 2025 study out of Wales that also just looked at vaccine eligibility… and not actual uptake. The media ran wild with that, too.
But back to the Canadians…
So just how much less likely were these folks to develop dementia?
Two percentage points.
Not 50 percentage points… or 20 points… or even 10 points.
Two.
This isn’t a dementia vaccine, as much as we all wish it was. You’d never want to call something a vaccine that only reduced your odds of developing a disease by two percentage points.
And the shingles vaccine they are hyping – Zostavax – has had plenty of problems with lawsuits over side effects. (Do yourself a favor and Google “Zostavax lawsuits” when we’re done here.)
Now, don’t get me wrong… no one is telling you to skip the shingles vaccine. That’s a personal decision you make with your doctor.
And if there was solid evidence that Zostavax or any shingles vaccine stopped dementia and was safe, you’d hear about it here first.
We’d be cheering right along with everyone else.
But despite the headlines, that’s not what this research found.
And it’s wrong to push people toward the shot under the guise of “dementia protection,” when that protection may not exist at all… and is minor if it does.
Delivering a shot of truth,
Ray Thatcher
Research Director, Health Sciences Institute
Sources:
- Eyting, M., Xie, M., Michalik, F., Heß, S., Chung, S., & Geldsetzer, P. (2025). A natural experiment on the effect of herpes zoster vaccination on dementia. Nature, 641, 438–446. https://doi.org/10.1038/s41586-025-08800-x
- George, J. (2026). Dementia and the Shingles Vaccine: What a New Study in Canada Found. MedPage Today. Retrieved January 27, 2026, from https://www.medpagetoday.com/neurology/dementia/119592?xid=nl_mpt_morningbreak2026-01-27
- Pomirchy, Michael et al. (2026) Herpes zoster vaccination and incident dementia in Canada: an analysis of natural experiments. The Lancet Neurology, Volume 25, Issue 2, 170 – 180
