Prevalence
of Overweight and Obesity Among Adults:
United States, 2003-2004
Results from the
2003-2004 National Health and Nutrition Examination Survey (NHANES), using
measured heights and weights, indicate that an estimated 66 percent of U.S.
adults are either overweight or obese as shown in table
1. One of the national
health objectives for 2010 is to reduce the prevalence of obesity among
adults to less than 15 percent. However, the NHANES 2003-2004 data for persons
age 20 years and over suggest an increase in the proportion of obese
adults in the United States, where the estimated age-adjusted prevalence moved
upward from a previous level of 23 percent in NHANES
III to a new level of approximately
32 percent.
Body mass
index (BMI),
expressed as weight/height2 (BMI; kg/m2), is
commonly used to classify overweight (BMI 25.0-29.9) and obesity (BMI
greater than or equal to 30.0) among adults (age 20 years and over).
Because NHANES II did not include individuals over 74
years of age, age-adjusted prevalence estimates for adults age 20-74 years were compared
in the NHANES surveys.There were notable
increases in the prevalence of persons who were either overweight or obese
(BMI greater than or equal to 25.0) in the last 25
years, as shown in table 2.
Most of this increase was attributable to increases in the obese category
(BMI greater than or equal to 30.0), whereas only minor increases occurred
in the prevalence of persons who are overweight but not obese (BMI
25.0-29.9).
NHANES used a stratified, multistage, probability
sample of the civilian, U.S. noninstitutionalized population. A household
interview and a physical examination were conducted for each survey
participant. During the physical examination, conducted in mobile
examination centers, height and weight were measured as part of a more
comprehensive set of body measurements. These measures were taken by
trained health technicians, using standardized measuring procedures and
equipment. Observations for pregnant women and for persons missing a valid
height or weight measurement were not included in the data analysis.
Table 1.
Age-adjusted* prevalence of overweight and obesity among U.S. adults among
U.S. adults, age 20 years and over
NHANES
III
(1988-94)
(n=16,679)
NHANES
(1999-2000)
(n=4,117)
NHANES
(2001-02) (n=4,413)
NHANES**
(2003-04) (n=4,431)
Overweight or obese (BMI
greater than or equal to 25.0)
56.0
64.5
65.7
66.3
Obese (BMI greater than or
equal to 30.0)
22.9
30.5
30.6
32.2
*Age-adjusted
by the direct method to the year 2000 U.S. Bureau of the Census estimates
using the age groups 20-39, 40-59, and 60 years and over. **Crude estimates (not age-adjusted) for 2003-4 are
66.5% with a BMI>=25 and 32.3% with a BMI>=30 printer friendly
Table 2.
Age-adjusted* prevalence of overweight and obesity among U.S. adults, age
20-74 years**
NHANES
II
(1976-80)
(n=11,207)
NHANES
III
(1988-94)
(n=14,468)
NHANES
(1999-2000)
(n=3,603)
NHANES
(2001-02)
(n=3,916)
NHANES
(2003-04)
(n=3,756)
Overweight or obese (BMI
greater than or equal to 25.0)
47.0
55.9
64.5
65.7
66.2
Obese (BMI greater than or
equal to 30.0)
15.0
23.2
30.9
31.3
32.9
*Age-adjusted
by the direct method to the year 2000 U.S. Bureau of the Census estimates
using the age groups 20-39, 40-59, and 60-74 years. **NHANES II did not include individuals over 74
years of age, thus trend estimates are based on age 20-74 years. printer friendly
Flegal KM,
Carroll MD, Ogden CL, Johnson CL. Prevalence and trends in obesity among US
adults, 1999-2000. JAMA 288:1723-7. 2002.
Ogden
CL, Carroll MD, Curtin LR, McDowell MA, Tabak CJ, Flegal KM.
Prevalence of overweight and obesity in the United States, 1999-2004. JAMA
295:1549-1555. 2006.