What percentage of adults are overweight?

According to the World Health Organization, 43% of adults worldwide were overweight in 2022 and 16% were living with obesity — and global obesity has more than doubled since 1990.

Does keeping a food diary help you lose weight?

Yes. In a Kaiser Permanente study of 1,685 adults, people who kept a daily food diary lost about twice as much weight as those who kept no records — one of the most consistent findings in weight-loss research.

Statistics

Nutrition & weight-loss statistics

The numbers behind diet and weight — every figure sourced from a health authority or peer-reviewed study. Free to cite, with links.

The obesity picture

43%

of adults worldwide were overweight in 2022

Source: WHO

16%

of the world's adults are living with obesity

Source: WHO

1B+

people now live with obesity — around 880 million adults and 159 million children

Source: World Obesity Federation

2×

global obesity has more than doubled since 1990

Source: WHO

40.3%

of US adults have obesity (2021–2023)

Source: CDC / NCHS

~50%

of adults could be living with a high BMI by 2030

Source: World Obesity Atlas 2025

How people are trying to change

49%

of US adults tried to lose weight in the past 12 months

Source: CDC / NCHS

1 in 10

US adults eat the recommended amount of vegetables

Source: CDC

+179

more calories a day than in 1977 — largely from food eaten away from home

Source: AJPM / portion research

What actually helps

2×

more weight lost by people who kept a daily food diary vs. those who didn't

Source: Kaiser Permanente

480%

bigger than the USDA serving — a typical US restaurant pasta portion

Source: Portion-size research

+30%

more calories eaten when portions are larger, with no increase in fullness

Source: Portion-size research

What the numbers tell us

Two things stand out: portions and eating out quietly push calories up, and the people who lose the most weight are the ones who track what they eat. Awareness is the lever. Browse the calories in common foods, print a food diary, or track by photo with LensNutra.

Nutrition & weight-loss statistics

The obesity picture

How people are trying to change

What actually helps

What the numbers tell us

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