Trends in obesity and abdominal obesity among adults in the United States from 1999-2008

The United States has experienced a large increase in the prevalence of obesity since the 1970s. Our objective was to describe recent trends in obesity and abdominal obesity among adults in the United States.

Trend study of cross-sectional studies.

We used data from up to 22,872 men and non-pregnant women aged ≥ 20 years from the National Health and Nutrition Examination Survey (NHANES) 1999-2008.

Main outcome measures are mean body mass index and waist circumference, percentages of obesity and abdominal obesity. Obesity was defined as a body mass index ≥ 30 kg m(-2), and abdominal obesity was defined as a waist circumference ≥ 102 cm in men and ≥ 88 cm in women.

In men, the age-adjusted mean body mass index, mean waist circumference, and prevalence of obesity and abdominal obesity were 27.8 kg m(-2), 99.1 cm, and 26.9 and 37.8%, respectively, during 1999-2000 and 28.5 kg m(-2) (P (trend) = 0.001), 100.8 cm (P (trend) = 0.002), and 32.0 (P (trend) = 0.001) and 43.7% (P (trend) = 0.002), respectively, during 2007-2008. In women, the age-adjusted mean body mass index, mean waist circumference, and prevalence of obesity and abdominal obesity were 28.2 kg m(-2), 92.2 cm, and 33.2 and 55.8%, respectively, during 1999-2000 and 28.6 kg m(-2) (P (trend) = 0.181), 94.9 cm (P (trend) = 0.006), and 35.2 (P (trend) = 0.180) and 61.8% (P (trend) = 0.036), respectively, during 2007-2008. Significant linear trends for increasing prevalence of obesity were noted among men with the least and most education.

Between 1999 and 2008, both obesity and abdominal obesity increased in men, and abdominal obesity increased in women.