Table 1.
General characteristics of study participants according to tertiles of dairy protein intake a at baseline.
| Men (n = 2096) | Women (n = 2316) | |||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Variables | T1 | T2 | T3 | p for Trend b | T1 | T2 | T3 | p for Trend | ||||||
| Mean | SD | Mean | SD | Mean | SD | Mean | SD | Mean | SD | Mean | SD | |||
| Age (years) | 50.9 | 8.2 | 49.1 | 7.5 | 50.4 | 7.9 | <0.001 | 52.8 | 9.0 | 49.4 | 7.9 | 50.6 | 8.1 | <0.001 |
| Residence area (% urban) | 58.9 | 70.8 | 74.9 | <0.001 | 42.8 | 68.8 | 69.4 | <0.001 | ||||||
| Education (% ≥College) | 18.8 | 27.8 | 29.8 | <0.001 | 3.7 | 10.0 | 10.1 | <0.001 | ||||||
| Household income (% ≥3,000,000 KRW) |
22.0 | 29.9 | 30.6 | <0.001 | 10.7 | 20.6 | 19.5 | <0.001 | ||||||
| Marital status (% married) | 96.9 | 96.8 | 97.3 | 0.640 | 86.1 | 90.1 | 87.6 | 0.380 | ||||||
| Dental health status (% poor) | 39.9 | 37.2 | 38.8 | 0.677 | 45.8 | 39.0 | 40.9 | 0.051 | ||||||
| Chronic disease (% yes) | 1.8 | 1.0 | 1.4 | 0.499 | 6.8 | 4.0 | 3.0 | <0.001 | ||||||
| Physical activity (METs-hours/day) |
23.9 | 15.5 | 21.8 | 13.4 | 22.5 | 13.4 | 0.020 | 24.4 | 15.1 | 20.9 | 12.9 | 21.7 | 13.1 | 0.021 |
| Alcohol consumption (% yes) | 72.3 | 76.4 | 72.8 | 0.819 | 22.7 | 26.8 | 29.5 | 0.002 | ||||||
| Smoking (% yes) | 50.0 | 43.8 | 40.1 | <0.001 | 2.9 | 1.6 | 2.5 | 0.633 | ||||||
| BMI (kg/m2) | 24.4 | 2.8 | 24.5 | 2.8 | 24.3 | 2.6 | 0.321 | 24.8 | 3.0 | 24.7 | 2.9 | 24.4 | 2.9 | 0.356 |
| Fat mass (kg) | 15.1 | 4.7 | 15.2 | 4.5 | 14.7 | 4.4 | 0.069 | 18.7 | 4.9 | 18.6 | 4.5 | 18.4 | 4.6 | 0.024 |
| Lean mass (kg) | 52.9 | 6.4 | 53.9 | 6.1 | 53.2 | 5.9 | 0.010 | 39.9 | 4.6 | 40.5 | 4.2 | 40.1 | 4.1 | 0.218 |
| SMI (%) | 40.6 | 2.6 | 40.7 | 2.4 | 40.9 | 2.4 | 0.068 | 35.6 | 2.6 | 35.8 | 2.4 | 35.8 | 2.6 | <0.001 |
BMI, body mass index; KRW, Korean won; MET, metabolic equivalent; SMI, skeletal muscle index. Data are presented as means ± standard deviations (SD) or n (%). a Protein intake from milk, yogurt, and cheese. b p for trend was calculated from a linear regression analysis for continuous variables and Mantel-Haenszel x2 for categorical variables.