The Complete Guide to
Dementia Prevention

Dementia is not inevitable. That's the most important sentence on this page, and it's backed by one of the largest bodies of research in modern medicine. The 2024 Lancet Commission on Dementia Prevention — the most comprehensive review of the evidence to date — concluded that up to 45% of dementia cases worldwide may be attributable to 14 modifiable risk factors. Modifiable means you can change them.

This doesn't mean you can guarantee prevention. Genetics play a role, and some risk factors are beyond your control. But the research is clear: the choices you make about how you move, eat, think, connect, and sleep have a significant, measurable effect on your brain's health as you age.

This guide covers what you need to know — the science, the risk factors, and what to actually do about them.

The 2024 Lancet Commission: the framework

The Lancet Commission on Dementia Prevention, Intervention, and Care has published three major reports (2017, 2020, 2024), each expanding the list of modifiable risk factors as the evidence has grown. The 2024 report, led by Gill Livingston and 27 co-authors, identified 14 factors — up from 12 in 2020 — and estimated their combined contribution at approximately 45% of all dementia cases globally.

This means that even if we can't eliminate dementia entirely, nearly half of all cases might never occur if these risk factors were fully addressed. In practice, even partial risk reduction across several factors adds up to meaningful protection.

The 14 modifiable risk factors

These are organized by life stage — when they have the most impact. Tap any factor to see what the research shows and what you can do about it.

Early life

Midlife (ages 40–65)

Late life (ages 65+)

The FINGER Trial: proof that intervention works

The Finnish Geriatric Intervention Study to Prevent Cognitive Impairment and Disability (FINGER) was the first large-scale randomized controlled trial to demonstrate that a multi-domain lifestyle intervention can improve or maintain cognitive function in at-risk older adults.

Published in The Lancet in 2015, the trial enrolled 1,260 adults aged 60–77 who were at elevated risk for cognitive decline. The intervention group received a combination of dietary guidance, physical exercise, cognitive training, and vascular risk monitoring. After two years, the intervention group showed significantly better cognitive performance than the control group.

FINGER has since spawned a global network of over 40 similar trials (the World-Wide FINGERS initiative) testing multi-domain interventions in different populations and contexts. The evidence base continues to grow.

The five domains: a framework for daily action

The 14 risk factors can feel overwhelming. To make them actionable, we organize brain-healthy habits into five daily practice domains. Each domain addresses multiple risk factors, and together they cover the full spectrum of what the research supports.

Dementia prevention by age

In your 40s: build the foundation

Midlife is when prevention has the most leverage. Cardiovascular fitness, blood pressure management, and establishing exercise and dietary habits now will pay dividends decades later. A study found that women with high midlife cardiovascular fitness had an 88% lower risk of dementia compared to those with low fitness.

In your 50s: manage the transitions

Metabolic changes (insulin resistance, blood pressure increases, hormonal shifts) make this decade critical. Get baseline screenings for blood pressure, cholesterol, blood sugar, hearing, and vision. Address anything that comes up — these are the years where risk factors compound if ignored.

In your 60s and beyond: it's not too late

The FINGER Trial proved that cognitive benefits are achievable in adults aged 60–77. The Erickson study showed hippocampal growth in adults with a mean age of 67. The ACHIEVE trial showed hearing aids slowed cognitive decline in adults aged 70–84. At every age studied, intervention helped.

What this guide won't tell you

We also won't tell you that supplements, brain training apps, or any single product is the answer. The research consistently points to lifestyle patterns — sustained, multi-domain habits practiced over time. There are no shortcuts, but there is a clear, evidence-backed path.

Where to start

If this guide has felt overwhelming, here are three things you can do this week:

Small, consistent actions across multiple areas of your life — that's what the research supports. Not perfection. Not panic. Just a steady, informed practice of taking care of your brain, one day at a time.

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