- by The Memory Exam Team
- July 20, 2026
New World Health Organization guidelines set out what actually reduces dementia risk, and which popular supplements do not.
On 15 July 2026 the World Health Organization published new guidelines on reducing the risk of cognitive decline and dementia. The headline finding is that up to 45% of dementia risk could be prevented or delayed by addressing modifiable risk factors.
That number deserves care in both directions. It does not mean 45% of dementia is preventable in any individual, and it does not mean anyone is to blame for developing it. What it means is that across a whole population, a substantial share of risk is attached to things that can change.
As WHO Director-General Dr Tedros Adhanom Ghebreyesus put it, "We know more today than ever before about what drives dementia risk, and these guidelines translate that knowledge into action."
The risk factors WHO names
The guidelines identify modifiable contributors to dementia risk, including:
- Tobacco use
- Alcohol consumption
- Physical inactivity
- Social isolation
- Air pollution
- Noncommunicable diseases, particularly high blood pressure and diabetes
Several of these are not individual choices at all. Air pollution is a matter of where you live, and social isolation is often a consequence of bereavement, mobility or income rather than preference. That is worth saying plainly, because risk-reduction advice can otherwise read as an accusation.
What WHO recommends
- Increasing physical activity
- Stopping tobacco use
- Reducing alcohol intake
- Eating a healthy diet
- Reducing exposure to air pollution
- Managing cardiometabolic conditions, including hypertension, diabetes and high cholesterol
- Considering hearing aids as part of risk reduction
- Cognitive training and cognitive stimulation
- Social engagement, for people with normal cognition and for those with mild cognitive impairment
Most of this is unglamorous, and most of it is the same advice that protects your heart. That overlap is not a coincidence.
What WHO does not recommend
This is the part worth reading twice.
WHO does not recommend vitamin B or vitamin E supplementation, omega-3 polyunsaturated fatty acids, or multivitamin and mineral supplements for reducing dementia risk in people without a diagnosed deficiency.
That runs against a great deal of popular advice, including some you will find on brain-health websites. If you are taking a supplement specifically to protect your memory, and you do not have a diagnosed deficiency, the current guidance does not support it. Talk to your doctor before changing anything you take.
We have written about omega-3 and brain health ourselves. We are reviewing that article against these guidelines, and we would rather say so than quietly leave it.
Where testing fits
One thing to be clear about: these guidelines are about risk reduction. They do not make recommendations about cognitive screening or early detection, and nothing here should be read as WHO endorsing any particular test, ours included.
What they do establish is that changes you make can matter. Which raises a practical question the guidelines do not answer: how would you know whether anything you are doing is working?
That is the argument for having a baseline. A single memory score tells you where you sit against people of your age and education. A score you can compare against your own result from a year ago tells you about direction, which is the thing risk reduction is actually trying to influence. If you want to read more, we have written about tracking memory over time.
The Memory Exam is a screening test, not a diagnosis, and it cannot tell you why anything has changed. That conversation belongs with your doctor.
Read the guidelines
The full WHO announcement is available on the World Health Organization website.
If you have noticed changes in your own memory or someone else's, our early warning signs checklist may help you describe them, and our page for caregivers is written for people worried about a parent.