Obesity Statistics: Prevalence, Health Risks, and Trends

40.3% of US adults had obesity and 9.4% had severe obesity in August 2021-August 2023

Measured heights and weights from NHANES. Obesity is a BMI of 30 or more; severe obesity 40 or more.

Adult obesity prevalence did not change significantly between 2013-2014 and 2021-2023, while severe obesity rose from 7.7% to 9.7%

Age-adjusted trend across NHANES cycles.

72.4% of US adults aged 20 and over had overweight, including obesity, in August 2021-August 2023

Overweight is a BMI of 25 or more.

Obesity affected 14.9% of US children aged 2-5, 22.1% of those aged 6-11 and 22.9% of adolescents aged 12-19 in 2021-2023

From NHANES; children's obesity is defined by BMI percentiles for age and sex.

In 2024, 45% of adults worldwide (2.6 billion) had overweight, and 940 million (16% of adults) had obesity

In 1990, 25% of adults had overweight.

Worldwide adult obesity has more than doubled since 1990, and among 5-19-year-olds obesity rose from 2% to 8% (170 million young people)

Adolescent obesity has quadrupled over the same period.

Adults with obesity had $2,505 (100%) higher annual medical costs than adults of normal weight, rising from 68.4% higher in class 1 obesity to 233.6% in class 3

Medical Expenditure Panel Survey 2001-2016, using children's BMI as an instrument to estimate causal costs; the aggregate was $260.6 billion in 2016. The study was funded by Novo Nordisk.

Each 5 BMI units above about 22.5-25 was associated with about 30% higher overall mortality (hazard ratio 1.29)

57 prospective studies with 894,576 participants, excluding the first 5 years of follow-up. The excess was mainly vascular disease.

Median survival was 2-4 years shorter at a BMI of 30-35 and 8-10 years shorter at 40-45, comparable with the effect of smoking

Same analysis; mortality was lowest at a BMI of about 22.5-25 in both sexes.

Among never-smokers without chronic disease, mortality hazard was 1.45 for grade 1 obesity, 1.94 for grade 2 and 2.76 for grade 3, against a BMI of 22.5-25

239 prospective studies on four continents with 10.6 million participants. Overweight carried smaller excess risks: 1.07 at BMI 25-27.5 and 1.20 at 27.5-30.

There is sufficient evidence that excess body fat raises the risk of 13 cancers, eight more than the five recognized in 2002

The eight added sites are gastric cardia, liver, gallbladder, pancreas, ovary, thyroid, multiple myeloma and meningioma, joining oesophageal adenocarcinoma, colorectal, postmenopausal breast, endometrial and kidney cancer.

A lifestyle programme aiming for at least 7% weight loss cut diabetes incidence by 58% in adults with raised blood glucose; metformin cut it by 31%

3,234 adults followed for an average of 2.8 years; 6.9 people needed the programme for three years to prevent one case.

Twelve years after gastric bypass, patients weighed 26.9% (35.0 kg) less than at baseline, and diabetes was in remission in 51% of those who had it

1,156 people with severe obesity in Utah, over 90% followed up. Those who sought surgery but did not have it lost 2.0%.

Weekly semaglutide 2.4 mg produced a 14.9% mean weight loss over 68 weeks, against 2.4% with placebo

1,961 adults without diabetes, both groups with lifestyle support; 50.5% on semaglutide lost at least 15%.

Weekly tirzepatide produced a 20.9% mean weight loss at 15 mg, 19.5% at 10 mg and 15.0% at 5 mg over 72 weeks, against 3.1% with placebo

2,539 adults with obesity or overweight plus a complication, without diabetes. 57% on 15 mg lost at least 20% of their weight.

Moving from 'inactive' to 'moderately inactive' was associated with 16-30% lower mortality across every BMI and waist-size group

334,161 European adults followed for 12.4 years. Avoiding all inactivity would in theory cut deaths by 7.35%, about twice the 3.66% from avoiding obesity.