The 14 Modifiable Risk Factors for Dementia — and What You Can Do About Them

For decades, dementia was widely understood as an inevitable consequence of ageing — a process that could not be meaningfully altered. That understanding has changed significantly. The 2024 Lancet Commission on Dementia Prevention, Intervention and Care identified fourteen modifiable risk factors that together account for approximately 45% of dementia cases globally. This means that nearly half of all dementia may be potentially preventable or delayed by addressing factors that are, to varying degrees, within our influence.

This does not mean that dementia is always preventable, or that people who develop it have failed to take adequate care of themselves. Genetics, age, and factors we cannot control remain significant. But it does mean that prevention-focused brain-health care is now supported by substantial evidence — and that the choices we make across the life course genuinely matter.

The Fourteen Modifiable Risk Factors

The Lancet Commission identified the following risk factors, roughly organised by the life stage at which they are most relevant to address:

Early life (before age 45)

1. Lower education. Less formal education in early life is associated with reduced cognitive reserve — the brain's capacity to compensate for damage or decline. Building cognitive reserve through lifelong learning, stimulating work, and intellectual engagement remains relevant at any age.

Midlife (ages 45–65)

2. Hearing loss. Untreated hearing loss is one of the most significant modifiable risk factors identified. It increases social isolation, reduces cognitive stimulation, and places additional cognitive load on the brain. Hearing assessment and appropriate intervention are underutilised prevention strategies.

3. High LDL cholesterol. Elevated LDL cholesterol in midlife is associated with increased dementia risk, likely through vascular mechanisms. Metabolic health management in midlife has long-term brain-health implications.

4. Depression. Depression is both a risk factor for dementia and an early symptom of it. The relationship is bidirectional and complex, but addressing depression — through appropriate care — is relevant to brain-health planning.

5. Traumatic brain injury. Head injuries, including concussion, are associated with increased dementia risk. Protective measures, appropriate recovery support, and addressing persistent post-concussion symptoms are all relevant.

6. Physical inactivity. Regular physical activity is one of the most consistently supported brain-health interventions in the research literature. It supports vascular health, reduces inflammation, promotes neuroplasticity, and improves sleep and mood.

7. Diabetes. Type 2 diabetes and insulin resistance are strongly associated with cognitive decline and dementia risk. Metabolic health management — including blood sugar regulation, diet, and movement — is a core component of prevention-focused brain-health care.

8. Hypertension. High blood pressure in midlife is a significant risk factor for vascular dementia and Alzheimer's disease. Blood pressure management — through lifestyle and, where appropriate, medical intervention — is one of the most evidence-supported prevention strategies.

Later life (age 65 and beyond)

9. Smoking. Smoking increases vascular risk, oxidative stress, and neuroinflammation — all of which are relevant to dementia risk. Cessation at any age is beneficial.

10. Obesity. Obesity — particularly abdominal adiposity — is associated with metabolic dysfunction, inflammation, and increased dementia risk. The relationship is complex, but metabolic health management remains relevant.

11. Excessive alcohol consumption. Heavy alcohol use is associated with direct neurotoxicity, nutritional deficiencies (particularly thiamine), and increased vascular risk. Reducing alcohol intake is a meaningful prevention strategy.

12. Air pollution. Exposure to fine particulate matter and air pollution is associated with increased dementia risk through neuroinflammatory and vascular mechanisms. Reducing exposure where possible — particularly for people living in high-pollution environments — is relevant.

13. Social isolation. Social isolation and loneliness are associated with increased dementia risk, likely through reduced cognitive stimulation, increased depression risk, and physiological stress responses. Maintaining social connection is a meaningful brain-health strategy at any age.

14. Vision loss. Untreated vision loss — like untreated hearing loss — is associated with increased dementia risk, likely through similar mechanisms of reduced sensory stimulation and increased cognitive load. Regular vision assessment and appropriate correction are underutilised prevention strategies.

"Nearly half of all dementia cases may be potentially preventable or delayed. That is not a reason for blame — it is a reason for optimism and action."

What This Means for You

The significance of this research is not that you need to address all fourteen factors simultaneously — that would be overwhelming and unrealistic. The significance is that there are meaningful, evidence-supported actions available at every stage of life. And that the earlier those actions are taken, the more cognitive reserve is built and maintained.

Prevention-focused brain-health care begins with understanding which factors are most relevant to your individual situation — your history, your current health patterns, your family context, and your goals. That is precisely what an assessment-led approach is designed to do.

Jo Grabyn's ClearPath Method considers the full range of modifiable contributors — not just the most obvious ones — and helps patients and families build a clearer, more structured picture of what is most worth addressing and in what order.