Table 1

Characteristics of study participants by quartile of dietary glycemic index in the JPHC Study
Quartile dietary glycemic index
1 2 3 4
Men (n = 27769)
Age,mean (SD) 55.5 (7.8) 56.3 (7.8) 56.6 (7.8) 57.5 (7.7)
Physical activity, metabolic equivalents -h/d, mean (SD)a 33.2 (6.7) 33.8 (6.7) 34.3 (6.8) 34.5 (6.8)
BMI, mean (SD)b 23.7 (2.9) 23.6 (2.8) 23.5 (2.8) 23.4 (2.8)
History of hypertension, % 14.3 16.8 18.0 18.7
Current smokersc, % 51.5 45.2 44.3 44.6
Occupationd, %
  Agriculture/forestry/fishery 21.6 27.6 31.6 37.4
  Salaried/self-employed/professional 65.0 59.4 54.9 49.9
  Housework/unemployed/retired 13.4 13.0 13.5 12.8
Dietary GI, mean (SD) 55 (4) 61 (1) 64 (1) 68 (2)
Dietary GL, mean (SD) 159 (59) 171 (50) 175 (51) 180 (56)
Total energy, kcal/d, mean (SD) 2460 (876) 2309 (699) 2174 (656) 1991 (626)
Carbohydrate, g/d, mean (SD) 302 (112) 294 (86) 285 (84) 274 (85)
Rice, g/d, mean (SD) 321.4 (154.5) 410.9 (151.7) 470.6 (170.5) 545.7 (199.5)
Rice with millet or barley, g/d, mean (SD) 24.2 (77.7) 26.7 (88.2) 25.2 (91.6) 20.7 (83.3)
Bread, g/d, mean (SD) 27.0 (34.7) 25.2 (36.2) 20.7 (35.7) 17.3 (51.0)
Udon, g/d, mean (SD) 73.9 (109.7) 58.4 (67.5) 45.1 (48.4) 29.1 (33.3)
Magnesium intake, mg/d, mean (SD) 349.4 (146.6) 312.7 (109.1) 277.7 (97.6) 231.6 (84.0)
Calcium, mg/d, mean (SD) 737 (497) 574 (284) 469 (220) 350 (177)
Dietary fiber, g/d, mean (SD) 15 (8) 13 (6) 12 (6) 9 (4)
Total fat, g/d, mean (SD) 75.2 (39.1) 64.4 (29.5) 55.0 (26.4) 42.3 (22.9)
Alcohol, g/week, (SD) 197.5 (241.9) 200.8 (235.8) 214.7 (243.2) 230.8 (249.3)
Coffee intake, almost nevere, % 15.8 22.8 32.1 51.7
Women (n = 36864)
Age,mean (SD) 55.3 (7.6) 56.1 (7.6) 57.2 (7.8) 58.9 (8.0)
Physical activity, metabolic equivalents -h/d, mean (SD)a 32.8 (5.7) 32.9 (5.7) 32.9 (5.8) 32.7 (5.8)
BMI, mean (SD)b 23.3 (3.0) 23.4 (3.0) 23.5 (3.1) 23.6 (3.2)
History of hypertension, % 15.1 16.8 19.2 22.9
Current smokersc, % 6.5 4.4 3.8 4.1
Occupationd, %
  Agriculture/forestry/fishery 16.2 22.8 27.4 32.2
  Salaried/self-employed/professional 42.5 37.0 32.8 27.8
  Housework/unemployed/retired 41.3 40.2 39.7 40.0
Dietary GI, mean (SD) 54 (3) 59 (1) 62 (1) 67 (2)
Dietary GL, mean (SD) 143 (53) 154 (43) 151 (39) 148 (44)
Total energy, kcal/d, mean (SD) 2215 (793) 2040 (598) 1835 (508) 1565 (509)
Carbohydrate, g/d, mean (SD) 283 (103) 276 (77) 256 (66) 232 (70)
Rice, g/d, mean (SD) 256.4 (126.1) 334.0 (117.8) 371.1 (120.7) 419.4 (142.8)
Rice with millet or barley, g/d, mean (SD) 24.8 (71.2) 27.6 (79.9) 27.1 (81.2) 21.6 (70.7)
Bread, g/d, mean (SD) 32.4 (32.8) 31.9 (39.8) 27.8 (43.5) 24.6 (59.1)
Udon, g/d, mean (SD) 62.5 (89.7) 52.0 (54.3) 41.0 (43.7) 27.1 (31.7)
Magnesium, mg/d, mean (SD) 355.8 (145.7) 312.2 (105.9) 269.8 (86.1) 211.2 (79.0)
Calcium, mg/d, mean (SD) 852 (530) 641 (280) 516 (219) 362 (181)
Dietary fiber, g/d, mean (SD) 18 (9) 16 (7) 13 (6) 10 (5)
Total fat, g/d, mean (SD) 78.5 (37.0) 66.0 (28.9) 55.6 (24.4) 41.8 (23.2)
Alcohol, g/week, (SD) 18.1 (69.0) 14.1 (62.4) 13.2 (63.3) 11.2 (56.8)
Coffee intake, almost nevere, % 13.4 20.8 30.3 47.2

an = 3117 for men and n = 30429 for women.

bn = 27205 for men n = 35972 for women.

cn = 27131 for men n = 34536 for women.

dn = 26876 for men, n = 35597 for women.

|en = 26325 for men, n = 34986 for women.

Oba et al.

Oba et al. Nutrition Journal 2013 12:165   doi:10.1186/1475-2891-12-165

Open Data