Demographic characteristics of study populations
| Total number of participants* | NHANES III (1988–1994) 16 533 % | NHANES 1999–2004 13 744 % | p Value |
| Age (years) | |||
| 20–39 | 46.2 | 40.2 | <0.001 |
| 40–59 | 31.2 | 38.6 | |
| 60+ | 22.7 | 21.2 | |
| Sex | |||
| Male | 47.6 | 48.0 | 0.47 |
| Female | 52.4 | 52.0 | |
| Race/ethnicity | |||
| NH White | 76.2 | 71.8 | 0.03 |
| NH African American | 11.0 | 11.1 | |
| Mexican American | 5.1 | 7.4 | |
| Other Race | 3.6 | 4.0 | |
| Other Hispanic | 4.1 | 5.8 | |
| Poverty to income ratio | |||
| ≤1.3 | 18.5 | 21.7 | <0.001 |
| >1.3 to < 3.5 | 45.4 | 36.2 | |
| ≥3.5 | 36.1 | 42.1 | |
| Education | |||
| Less than high school | 24.9 | 20.4 | <0.001 |
| High school graduate | 33.7 | 26.2 | |
| Some college or higher | 41.4 | 53.4 | |
| BMI† | |||
| Normal (<25) | 44.9 | 34.3 | <0.001 |
| Overweight (≥25 to <30) | 32.7 | 34.8 | |
| Obese (≥30 to <35) | 14.5 | 18.5 | |
| Severely obese (≥35) | 7.9 | 12.4 | |
| Waist circumference† | <0.001 | ||
| ≤88 cm (women), ≤102 cm (men) | 62.6 | 51.1 | |
| >88 cm (women), >102 cm (men) | 37.4 | 48.9 | |
| Physical activity, Category† | |||
| Inactive | 24.9 | 36.8 | <0.001 |
| Insufficiently active | 34.1 | 25.3 | |
| Active | 41.1 | 37.9 | |
| Alcohol use | |||
| 0 drinks/day | 45.7 | 37.2 | <0.001 |
| 1–2 drinks/day | 30.1 | 37.7 | |
| ≥3 drinks/day | 24.3 | 25.1 | |
| Smoking | |||
| Never | 45.9 | 49.9 | <0.001 |
| Former | 25.7 | 25.0 | |
| Current | 28.3 | 25.1 | |
| Current health status | |||
| Excellent | 20.4 | 21.6 | 0.08 |
| Very good | 30.9 | 31.0 | |
| Good | 32.8 | 30.3 | |
| Fair | 12.9 | 13.5 | |
| Poor | 3.0 | 3.6 | |
| Cancer history | |||
| No | 92.2 | 92.0 | |
| Yes | 7.8 | 8.0 | 0.70 |
| Diabetes | |||
| No | 94.5 | 93.0 | |
| Yes | 5.5 | 7.0 | <0.001 |
| Heart disease | |||
| No | 94.1 | 93.7 | |
| Yes | 5.9 | 6.3 | 0.42 |
| Chronic kidney disease | |||
| No | 94.4 | 92.8 | |
| Yes | 5.6 | 7.2 | <0.001 |
*Number of participants with missing data varies across demographic variables.†Excludes pregnant women.
BMI, body mass index; cm, centimetre; NH, Non-Hispanic; NHANES, National Health And Nutrition Examination Survey.