Table 1.
Characteristics of 22,120 Participants According to Dairy and Soy Intake, Black Women's Health Study, United States, 1997–2007a
| High-fat Dairy, Servings/Week |
Low-fat Dairy, Servings/Week |
Soy, Servings/Weekb |
|||||||
| <1 | 4–6 | ≥14 | <1 | 4–6 | ≥14 | <1 | 4–6 | ≥7 | |
| No. of women | 7,388 | 2,917 | 606 | 9,051 | 2,716 | 1,319 | 9,290 | 266 | 361 |
| Age, years (mean) | 35.5 | 33.9 | 32.0 | 34.8 | 34.5 | 34.6 | 34.0 | 33.2 | 34.7 |
| Body mass index, kg/m2 (mean) | 27.5 | 28.1 | 28.1 | 27.2 | 28.5 | 28.9 | 27.9 | 26.0 | 25.5 |
| Age at menarche, years (mean) | 12.3 | 12.3 | 12.5 | 12.4 | 12.2 | 12.3 | 12.3 | 12.2 | 12.3 |
| Parous (%) | 53.6 | 58.8 | 71.4 | 58.9 | 54.1 | 58.0 | 56.2 | 40.3 | 42.9 |
| Age at first birth for parous women, years (mean) | 23.2 | 23.2 | 22.4 | 22.8 | 23.4 | 23.8 | 23.6 | 23.6 | 24.9 |
| Time since last birth for parous women, years (mean) | 10.3 | 9.7 | 9.0 | 10.4 | 9.8 | 9.6 | 9.2 | 9.5 | 8.5 |
| Vigorous exercise, hours/week (mean) | 1.9 | 1.5 | 1.3 | 1.4 | 1.8 | 2.2 | 1.6 | 2.5 | 2.5 |
| Age at first oral contraceptives use for ever users, years (mean) | 19.4 | 19.2 | 19.1 | 19.3 | 19.2 | 19.2 | 19.2 | 18.9 | 18.9 |
| Alcohol intake, drinks/week (mean) | 1.2 | 1.4 | 1.4 | 1.5 | 1.2 | 1.2 | 1.2 | 0.9 | 1.1 |
| Current smoker (%) | 10.8 | 16.5 | 20.0 | 17.0 | 11.0 | 11.1 | 12.8 | 5.3 | 6.1 |
| Dairy foods intake, servings/week | 4.2 | 9.2 | 27.3 | 3.5 | 8.2 | 27.9 | 7.1 | 7.9 | 9.2 |
| Soy foods intake, servings/week | 0.8 | 0.6 | 0.4 | 0.5 | 0.8 | 1.2 | 0.1 | 5.2 | 15.1 |
| Energy intake, kcal/day (mean) | 1,294 | 1,943 | 2,554 | 1,506 | 1,671 | 2,223 | 1,624 | 1,572 | 1,724 |
| Multivitamin supplements use (%) | 71.8 | 71.8 | 71.3 | 66.0 | 74.0 | 80.0 | 68.9 | 81.0 | 84.6 |
| Calcium supplement use (%) | 15.9 | 15.1 | 15.9 | 13.0 | 13.7 | 15.8 | 12.0 | 23.2 | 29.3 |
| Calcium with vitamin D use (%) | 9.8 | 7.3 | 7.9 | 6.7 | 9.4 | 11.5 | 6.8 | 9.3 | 12.2 |
| Diabetes (%) | 3.0 | 2.9 | 1.8 | 2.7 | 3.2 | 4.3 | 2.8 | 2.3 | 1.5 |
| Education in 1995, years (mean) | 15.0 | 14.8 | 14.1 | 14.7 | 15.1 | 15.1 | 15.0 | 15.6 | 15.6 |
| Married (%) | 39.9 | 39.4 | 38.6 | 38.7 | 40.7 | 41.9 | 40.6 | 32.4 | 37.2 |
| Household income in 2003 (%) | |||||||||
| ≤$25,000 | 9.4 | 9.8 | 21.4 | 12.4 | 7.8 | 10.6 | 9.9 | 7.4 | 8.5 |
| $25,001–$50,000 | 29.8 | 34.5 | 35.3 | 32.3 | 29.7 | 29.4 | 31.2 | 28.5 | 29.7 |
| $50,001–$100,000 | 41.1 | 37.8 | 33.0 | 39.7 | 41.8 | 38.8 | 39.9 | 44.2 | 40.3 |
| >$100,000 | 19.8 | 17.9 | 10.3 | 15.6 | 20.8 | 21.3 | 19.0 | 19.9 | 21.5 |
| Occupation in 1995 (%) | |||||||||
| White collar | 60.6 | 58.8 | 43.4 | 54.6 | 65.3 | 61.6 | 60.3 | 74.5 | 68.0 |
| Non-white-collar | 37.7 | 38.9 | 51.4 | 42.9 | 33.3 | 36.0 | 37.6 | 25.0 | 31.0 |
| Not employed and other | 1.8 | 2.3 | 5.2 | 2.6 | 1.4 | 2.5 | 2.1 | 0.5 | 1.0 |
| Region of residence in the United States (%) | |||||||||
| Northeast | 24.5 | 29.8 | 34.3 | 28.3 | 26.4 | 25.8 | 26.2 | 32.0 | 33.0 |
| Midwest | 22.1 | 21.3 | 19.3 | 20.1 | 22.8 | 27.0 | 23.8 | 15.7 | 15.6 |
| South | 34.3 | 30.2 | 30.8 | 34.0 | 32.0 | 29.3 | 32.9 | 29.4 | 27.6 |
| West | 19.1 | 18.7 | 15.6 | 17.6 | 18.7 | 16.9 | 17.1 | 22.9 | 23.9 |
a
Means and percentages were standardized to the age distribution of the cohort in 1997. Variables reported at the start of follow-up unless otherwise noted.
b
Restricted to 10,786 participants who completed a 2001 food frequency questionnaire (on which they were asked about soy products) and who were still at risk of uterine leiomyomata in 2001.