Table 1

Characteristics of study population in the lowest to highest quartiles of different dietary protein intake
Total protein intake (% of total energy intake) Animal protein intake (% of total energy intake) Plant protein intake (% of total energy intake)
Characteristics Q1 (<10.1%) Q2 (10.1-12.8%) Q3 (12.9-15.9%) Q4 (>15.9%) Pa Q1 (<3.7%) Q2 (3.7-5.6%) Q3 (5.7-8.4%) Q4 (>8.4%) Pa Q1 (<4.9%) Q2 (4.9-6.6%) Q3 (6.7-8.4%) Q4 (>8.4%) Pa
n 254 254 254 253 254 254 254 253 254 254 254 253
Age, y 61 ± 11 62 ± 12 62 ± 11 61 ± 12 0.48 61 ± 11 62 ± 11 62 ± 11 61 ± 12 0.47 60 ± 12 61 ± 11 62 ± 11 63 ± 11 0.01
Male, n (%) 138(54) 162(63) 164(64) 188(74) <0.001 139(54) 175(68) 162(63) 176(69) 0.002 195(76) 169(66) 146(57) 142(56) <0.001
BMI, kg/m2 24.7 ± 3.9 24.6 ± 3.9 24.2 ± 3.8 24.3 ± 3.7 0.39 24.6 ± 3.5 24.5 ± 4.0 24.5 ± 4.2 24.2 ± 3.7 0.73 24.9 ± 3.9 24.2 ± 4.0 24.5 ± 4.0 24.3 ± 3.4 0.15
WHR 0.97 ± 0.06 0.93 ± 0.08 1.01 ± 0.07 0.91 ± 0.07 0.27 1.01 ± 0.08 0.97 ± 0.06 0.92 ± 0.06 0.91 ± 0.07 0.23 0.94 ± 0.07 0.92 ± 0.06 0.96 ± 0.09 0.93 ± 0.07 0.28
Total energy intake, MJ/d 8.1 ± 3.4 8.2 ± 4.2 9.2 ± 5.3 11.2 ± 5.8 <0.001 9.3 ± 4.5 9.4 ± 4.8 8.7 ± 4.1 9.0 ± 5.2 0.21 12.0 ± 5.7 9.2 ± 4.4 7.9 ± 3.3 7.5 ± 3.6 0.001
Total fat intake,% of total energy intake 23.5 ± 11.7 30.0 ± 9.7 29.8 ± 8.8 31.1 ± 8.6 <0.001 24.4 ± 11.1 28.2 ± 9.2 30.2 ± 9.4 31.6 ± 9.5 <0.001 26.6 ± 13.5 29.2 ± 9.5 28.9 ± 8.3 29.8 ± 8.2 0.30
Smoker, n (%) 151(59) 117(46) 98(38) 87(34) <0.001 137(53) 106(41) 116(45) 94(37) 0.001 158(62) 115(45) 92(36) 88(34) 0.001
Alcohol user, n (%) 191(75) 137(54) 109(42) 98(38) <0.001 74(29) 54(21) 53(20) 39(15) 0.003 87(34) 57(22) 41(16) 35(13) <0.001
Tea user, n (%) 112(21) 129(24) 136(25) 158(30) <0.001 117(22) 112(44) 155(61) 151(59) 0.005 197(77) 147(57) 108(42) 83(32) 0.001
Family history of CAD, n (%) 12(4.7) 19(7.5) 8(3.1) 17(6.7) 0.12 9(3.5) 17(6.7) 16(6.3) 14(5.5) 0.41 14(5.5) 11(4.3) 17(6.7) 14(5.5) 0.71
Hypertension, n (%) 167(64) 170(67) 154(60) 147(57) 0.12 165(65) 166(65) 162(63) 142(56) 0.10 155(61) 158(62) 162(63) 160(63) 0.92
Hyperlipidmia, n (%) 27(10) 42(16) 39(15) 34(13) 0.24 33(13) 35(13) 36(14) 38(15) 0.93 31(12) 36(14) 35(13) 40(15) 0.70
Diabetes, n (%) 61(24) 61(24) 56(22) 62(24) 0.90 67(26) 60(23) 59(23) 54(21) 0.61 60(23) 49(19) 64(25) 67(26) 0.24

Values are means ± SD or n (%).

aP-value was based on ANOVA when row variable was continuous (age, BMI, WHR, total energy intake, and total fat intake) and χ2 test when row variable was categorical.

Xiao et al.

Xiao et al. Nutrition Journal 2013 12:144   doi:10.1186/1475-2891-12-144

Open Data