Table 1.

Descriptive Statistics of the Sample by Survey Period

	NHANES Survey Period
	1988–1994	1999–2002	2003–2006	2007–2010	2011–2014
N	8,494	5,278	5,167	6,857	6,354
Age, years	52.9	52.5	53.0	53.3	54.0
Sex, male	47.9	48.8	48.4	49.0	48.5
Race/ethnicity
Non-Hispanic white	80.4	75.6	76.2	73.2	69.9
Non-Hispanic black	9.2	9.6	10.1	10.0	10.3
Hispanic	7.6	11.5	9.0	10.8	12.5
Other	2.8	3.4	4.7	6.0	7.3
Education
Less than high school	25.2	20.9	16.1	18.3	15.6
High school	33.7	25.1	26.7	24.1	20.8
More than high school	41.1	54.1	57.2	57.7	63.6
Smoking Status
Never	41.1	46.6	47.2	51.7	52.7
Former	33.6	30.9	29.5	28.5	27.8
Current	25.3	22.5	23.3	19.8	19.5
Abdominal Adiposity
Weight Circumference, cm	95.2	97.9	99.5	100.2	101.2
General Adiposity
Current BMI, kg/m2	27.3	28.4	28.9	29.1	29.3
BMI 10 Years Prior, kg/m2	25.5	26.1	26.7	27.0	27.7
BMI at Age 25, kg/m2	23.1	23.4	23.7	23.9	24.3
Maximum BMI, kg/m2	29.3	30.5	31.2	31.3	31.9

BMI: Body mass index. Never smokers are defined as individuals who reported smoking less than 100 cigarettes during their lifetime. BMI and waist circumference were measured in the examination component of the NHANES. BMI was calculated using data on height and weight. BMI 10 years prior, at age 25 and at maximum were calculated using recalled data on weight combined with height measured at the time of the survey. Estimates are adjusted for sample weights.