‹ M. Eric Cui

Based on the Lancet Commission

Dementia risk check

Nearly half of dementia cases are linked to 14 things people can change. See which apply to you, and what helps.

Start the checkHow to read it ›

Which apply to you?

Three short steps. Every question uses the Commission’s own definition. Nothing you choose leaves this page.

Step 1

Before you start

  • This is an awareness tool, not a medical test. It can’t diagnose dementia, predict whether you’ll get it, or tell you your personal risk.
  • The numbers describe dementia across the world’s population. They’re simplified here and may not apply to you.
  • It isn’t medical advice. If you’re worried about your memory or health, talk to a doctor.
Full disclaimer

This tool is provided “as is” for general information and education only, to raise awareness of dementia risk factors. It is not a medical device and does not provide medical advice, diagnosis, treatment or a personal risk assessment. The figures are population estimates from published research (Livingston et al., The Lancet, 2017, 2020 and 2024), simplified for a general audience; they may contain errors, may become out of date, and may not apply to any individual.

Always seek the advice of a doctor or other qualified health professional with any questions about your health. Never disregard professional advice, or delay seeking it, because of anything on this page. If you think you may have a medical emergency, contact your local emergency services.

To the fullest extent permitted by law, M. Eric Cui makes no warranties of any kind, express or implied, about the accuracy, completeness or suitability of this tool, and accepts no liability for any loss, injury or damage arising from its use or from reliance on it.

Your answers are handled only in your browser and are not sent, stored or shared. This is a personal project, not affiliated with or endorsed by The Lancet, the Commission’s authors, or any institution the author works with.

Step 2

How old are you?

The Commission groups risks by stage of life: early life (under 45), midlife (45 to 65) and later life (over 65). Stages you haven’t reached stay blank.

Step 3

Your answers

Tap a bubble, or open a stage of life below. A bigger bubble means more cases.

The circle is 100 people with dementia worldwide — a share of cases, not your personal risk.

  • What you picked
  • Other changeable factors
  • Age, genes and causes not yet known

How to read this

What the numbers mean, in plain words.

  • It’s about everyone, not just you

    “7 in 100” means that if hearing loss vanished worldwide, about 7 in every 100 dementia cases might be prevented or delayed. It doesn’t mean you have a 7% chance.

  • Never too early or too late

    Each factor sits in the stage of life where its evidence is strongest — early life (under 45), midlife (45 to 65) or later life (over 65) — but the Commission found acting at any age can help.

  • Healthy habits add up

    In the FINGER trial, two years of better diet, exercise, brain training and heart-health checks helped older adults at risk keep their thinking sharper.

  • The shares are estimates

    The Commission adjusted the 14 shares for how risks overlap, so adding a few together gives a rough figure. Age, genes and causes not yet known account for the other 55.

Credit & sources

The 14 factors and their shares come from the Lancet Commission’s 2024 report; definitions come from the Commission’s reports, cited under each question. This page is an interactive retelling of their risk factors infographic.

  • The 14 risk factors, their shares, and recommendationsLivingston G, Huntley J, Liu KY, et al. Dementia prevention, intervention, and care: 2024 report of the Lancet standing Commission. The Lancet 2024. doi:10.1016/S0140-6736(24)01296-0
  • Life stages, hearing, head injury, blood pressure, obesity, activity, air pollutionLivingston G, Huntley J, Sommerlad A, et al. Dementia prevention, intervention, and care: 2020 report of the Lancet Commission. The Lancet 2020. doi:10.1016/S0140-6736(20)30367-6
  • Less education (none or primary school only)Livingston G, Sommerlad A, Orgeta V, et al. Dementia prevention, intervention, and care. The Lancet 2017. doi:10.1016/S0140-6736(17)31363-6
  • Everyday definitions where the Commission’s public text gives none (depression, isolation)The potential for dementia prevention in Brazil: a population attributable fraction calculation for 14 modifiable risk factors — co-authored by Commission members, following the 2024 definitions. 2025. PMC12355584
  • Hearing · ACHIEVE trialLin FR, et al. Hearing intervention versus health education control to reduce cognitive decline in older adults with hearing loss in the USA (ACHIEVE). The Lancet 2023. doi:10.1016/S0140-6736(23)01406-X
  • Blood pressure · SPRINT MIND trialThe SPRINT MIND Investigators. Effect of intensive vs standard blood pressure control on probable dementia. JAMA 2019. doi:10.1001/jama.2018.21442
  • Vision · cataract surgeryLee CS, et al. Association between cataract extraction and development of dementia. JAMA Internal Medicine 2022. doi:10.1001/jamainternmed.2021.6990
  • Healthy habits together · FINGER trialNgandu T, et al. A 2 year multidomain intervention of diet, exercise, cognitive training, and vascular risk monitoring versus control to prevent cognitive decline in at-risk elderly people (FINGER). The Lancet 2015. doi:10.1016/S0140-6736(15)60461-5

Built independently by M. Eric Cui; not affiliated with or endorsed by The Lancet or the authors above. Questions, definitions and advice are simplified for a general audience. For awareness only — not medical advice.