The National Center for Health Statistics (NCHS) has issued one of its periodic reports, “Prevalence of overweight, obesity and extreme obesity among adults: United States Trends 1960-1962 Through 2009-2010.” The results of the 2009-2010 NHANES show that 33% of US adults are overweight, 35.7% are obese and 6.3% are extremely obese (defined as a BMI of 40 or more.) In 1988-1994, the prevalence of adult obesity was 23%. The prevalence of obesity among adults 20-74 more than doubled between 1976-1980 and 2009-2010 while the prevalence of overweight was basically stable.
Extreme obesity has increased among adults age 20-74 from 0.9% in 1960-1962 to 6.6% in 2009-2010. Among men, the prevalence has changed from 0.3% to 4.6%; among women from 1.4% to 8.5%.