All factors

Obesity

Midlife obesity (BMI 30+) increases dementia risk by 30-40% through inflammation, insulin resistance and vascular damage.

Population risk0.7%
Evidence gradecohort

Why it matters

Even modest weight loss (5-10%) reduces inflammation and improves blood sugar control, both of which protect the brain.

What to ask at the checkup

Ask whether a weight management plan would be appropriate

Screening: BMI calculation

Sources

Dementia prevention, intervention, and care: 2024 report of the Lancet Commission

Livingston G, Huntley J, Liu KY et al.. The Lancet, 2024.

Fourteen things people can change account for nearly half of dementia cases at the population level.

Body mass index and risk of dementia: a systematic review and meta-analysis

Singh-Manoux A, Dugravot A, Shipley M et al.. BMJ, 2018.

Being obese in middle age raised dementia risk by about a third compared to a healthy weight.

Routines for this factor

Step on the scale this week

Weigh in once this week and record the number.

2 min, difficulty 1/3

Take the stairs once today

Choose stairs over the elevator or escalator for one trip.

2 min, difficulty 2/3