Skip to content
obesitysurvey
Menu

Learn ❤️

Why obesity matters for health

Obesity raises the risk of diabetes, heart disease and other illnesses. What WHO and the World Obesity Federation say, and what the data shows.

Health organisations track obesity because it makes several serious illnesses more likely. Here is what they report.

3.7 million

deaths from noncommunicable diseases in 2021 were caused by higher-than-optimal BMI, WHO estimates.
Source: World Health Organization, Obesity and overweight (fact sheet) (8 December 2025)

1.6 million

deaths before age 70 from diseases like diabetes, cancer and stroke were directly attributable to high BMI in 2021.
Source: World Obesity Federation, World Obesity Atlas 2025 (March 2025)

Early risk

Overweight in childhood is linked to a greater risk, and earlier onset, of diseases like type 2 diabetes and heart disease.
Source: World Health Organization, Obesity and overweight (fact sheet) (8 December 2025)

US$3 trillion

a year — the predicted global cost of overweight and obesity by 2030, rising to more than US$18 trillion by 2060.
Source: World Health Organization, Obesity and overweight (fact sheet) (8 December 2025)

Obesity and diabetes, side by side

Worldwide, the share of adults with diabetes has risen over the same years as obesity. Rising together does not by itself prove that one causes the other — but type 2 diabetes is one of the diseases WHO links to overweight (see the cards above).

World: adults with obesity

What this means6.7% in 1990 → 15.4% in 2022.

0%5%10%15%20%1990199520002005201020152020Obesity 15.4%

World: adults with diabetes

What this means6.8% in 1990 → 14.1% in 2022.

0%5%10%15%20%1990199520002005201020152020Diabetes 14.1%

Both charts show age-standardized WHO estimates for adults 18+. They are drawn separately on purpose: they measure different things.

Last updated

Written by the ObesitySurvey team. Not medical advice.

Keep learning