Table 1.
| Table 1a. Age-standardized* characteristics by weight change since 18 years in the Nurses' Health Study I, 1980-2008 | ||||||
|---|---|---|---|---|---|---|
| Weight Loss, kg | Weight loss or gain | Weight gain, kg | ||||
| Characteristic | ≥ 5.0 | 2.0 – 4.9 | < 2.0 kg | 2.0 – 9.9 | 10.0 – 19.9 | ≥ 20.0 |
| Person-years | 18,342 | 17,190 | 30,532 | 119,060 | 77,754 | 42,992 |
| Age, mean, y | 44.2 | 44.2 | 44.2 | 45.1 | 46.5 | 47.3 |
| Age at menarche | 12.3 | 12.4 | 12.4 | 12.4 | 12.3 | 12.1 |
| Current oral contraceptive use‡, % | 0.8 | 0.7 | 0.8 | 0.7 | 0.6 | 0.3 |
| Nulliparous, % | 7.7 | 6.1 | 5.8 | 5.3 | 5.1 | 5.1 |
| Number of children, mean† | 2.8 | 2.9 | 2.9 | 3.0 | 3.0 | 3.0 |
| Age at first birth, mean, y† | 24.6 | 24.4 | 24.3 | 24.3 | 24.2 | 24.1 |
| Family history of breast cancer, % | 7.4 | 6.6 | 7.1 | 6.8 | 6.8 | 7.0 |
| History of benign breast disease, % | 36.2 | 37.6 | 38.2 | 35.8 | 31.7 | 27.8 |
| Weight at 18 y, mean, kg | 69.0 | 60.4 | 56.8 | 55.7 | 56.4 | 60.4 |
| Body mass index at 18 y, mean kg/m2 | 25.6 | 22.5 | 21.3 | 20.7 | 20.9 | 22.2 |
| Body mass index, mean, kg/m2 | 23.0 | 22.2 | 22.1 | 23.6 | 26.8 | 33.3 |
| Height, mean, m | 1.64 | 1.64 | 1.63 | 1.64 | 1.64 | 1.65 |
| Alcohol intake, mean, g/d | 6.7 | 7.0 | 6.8 | 6.2 | 5.0 | 3.4 |
| Physical activity ≥ 4 METs/d, % | 24.4 | 23.0 | 22.5 | 18.5 | 14.4 | 11.1 |
|
| ||||||
| * Age-standardized to the age distribution of the study population during follow-up 1980-2008 | ||||||
| † Among parous women only | ||||||
| ‡ Data available on current oral contraceptive use is only available until 1984. | ||||||
| Table 1b. Age-standardized* characteristics by weight change since 18 years in the Nurses' Health Study II, 1993-2007 | ||||||
|---|---|---|---|---|---|---|
| Weight Loss, kg | Weight loss or gain | Weight gain, kg | ||||
| Characteristic | ≥ 5.0 | 2.0 – 4.9 | < 2.0 kg | 2.0 – 9.9 | 10.0 – 19.9 | ≥ 20.0 |
| Person-years | 25,214 | 24,819 | 49,239 | 261,311 | 253,965 | 225,287 |
| Age, mean, y | 40.9 | 40.8 | 41.1 | 41.7 | 43.2 | 44.2 |
| Age at menarche, mean, y | 12.4 | 12.5 | 12.6 | 12.6 | 12.4 | 12.1 |
| Oral contraceptive use, % | 8.9 | 9.0 | 8.8 | 9.1 | 8.3 | 6.6 |
| Nulliparous, % | 31.7 | 23.4 | 20.2 | 18.3 | 16.4 | 20.0 |
| Number of children, mean† | 2.2 | 2.3 | 2.3 | 2.3 | 2.3 | 2.3 |
| Age at first birth, mean, y† | 27.2 | 27.1 | 27.1 | 26.9 | 26.5 | 26.0 |
| Family history of breast cancer, % | 8.9 | 8.2 | 8.6 | 8.8 | 8.8 | 8.7 |
| History of benign breast disease, % | 44.9 | 44.7 | 45.4 | 44.1 | 41.7 | 38.5 |
| Weight at 18 y, mean, kg | 71.9 | 61.0 | 56.6 | 55.3 | 56.7 | 62.1 |
| Body mass index at 18 y, mean kg/m2 | 26.4 | 22.6 | 21.0 | 20.4 | 20.8 | 22.5 |
| Body mass index, mean, kg/m2 | 24.1 | 22.4 | 22.0 | 23.5 | 27.1 | 34.5 |
| Height, mean, m | 1.65 | 1.64 | 1.64 | 1.65 | 1.65 | 1.66 |
| Alcohol intake, mean, g/d | 4.3 | 5.0 | 4.7 | 4.4 | 3.7 | 2.5 |
| Physical activity ≥ 4 METs/d, % | 28.7 | 28.9 | 26.8 | 23.0 | 17.7 | 11.8 |
*
Age-standardized to the age distribution of the study population during follow-up 1993-2007
†
Among parous women only