Table 1. Characteristics of the twins.
| All | MZ twins | DZ twins | |
| No. of individuals | 400 | 200 | 200 |
| Post-menopausal (%) | 64 (16) | 32 (16) | 32 (16) |
| Age (y) | 47.8±9.3 | 47.6±9.6 | 48.1±9.1 |
| (28.6, 72.8) | (28.6, 72.6) | (33.5, 72.8) | |
| BMI (kg/m2) | 24.9±24.8 | 24.8±4.6 | 24.9±5.2 |
| (16.5, 44.4) | (17, 44.4) | (16.5, 43.5) | |
| Smoking status: | |||
| Never (%) | 249 (62.3) | 136 (68.0) | 113 (56.5) |
| Former (%) | 107 (26.8) | 45 (22.5) | 62 (31.0) |
| Current (%) | 44 (11.0) | 19 (9.5) | 25 (12.5) |
| C-reactive protein (mg/l) | 2.83±4.37 | 2.34±2.93 | 3.31±5.39 |
| (n = 136 MZ, 140 DZ) | (0.16, 34) | (0.16, 20.9) | (0.16, 34.0) |
| Dietary calcium | 1074±328 | 1070±324 | 1078±333 |
| (mg/day) | (232, 2119) | (232, 2010) | (232, 2119) |
| Dietary fibre (g/day) | 19.1±7.1 | 19.3±6.9 | 18.9±7.2 |
| (5.3, 51.0) | (5.3, 51.0) | (5.4, 50.5) | |
| Dietary vitamin C | 154.9±77.9 | 160.4±77.1 | 149.4±78.5 |
| (mg/day) | (31.0, 561) | (41.2, 515) | (31.0, 561) |
| Meat consumption | 2.0±1.72 | 1.9±1.5 | 2.2±1.9 |
| (times/week) | (0, 11.5) | (0, 8.75) | (0, 11.5) |
Values are means ± SD (min, max).