Table 2 General characteristics of study participants by nut consumption frequency, N (%)
From: The relationship between nut intake and risk of colorectal cancer: a case control study
|  | Men (n = 1875) |  | Women (n = 894) |  | ||||||
|---|---|---|---|---|---|---|---|---|---|---|
Variable | None | < 1 serving per week | 1–3 servings per week | ≥3 servings per week | P-valuea | None | < 1 serving per week | 1–3 servings per week | ≥3 servings per week | P-valuea |
Number | 682 | 855 | 163 | 175 | Â | 280 | 413 | 85 | 116 | Â |
Age (years) b | 56.1 ± 9.4 | 57.0 ± 8.8 | 57.4 ± 8.2 | 58.0 ± 8.3 | 0.032 | 54.4 ± 11.0 | 55.4 ± 9.6 | 53.1 ± 9.0 | 56.5 ± 8.8 | 0.060 |
Marital status | Â | Â | Â | Â | 0.706 | Â | Â | Â | Â | 0.028 |
 Married | 622(91.2) | 790(92.4) | 149(91.4) | 158(90.2) |  | 212(75.7) | 323(78.2) | 76(89.4) | 98(84.5) |  |
 Single | 56(8.2) | 57(6.7) | 13(8.0) | 12(6.9) |  | 65(23.2) | 87(21.1) | 9(10.6) | 17(15.7) |  |
 Missing | 4(0.6) | 8(0.9) | 1(0.6) | 5(2.9) |  | 3(1.1) | 3(0.7) | 0(0.0) | 1(0.8) |  |
Education level | Â | Â | Â | Â | 0.001 | Â | Â | Â | Â | <.001 |
 Less than high school | 149(21.9) | 156(18.2) | 23(14.1) | 30(17.1) |  | 104(37.1) | 113(27.4) | 9(10.6) | 18(15.5) |  |
 High school | 241(35.3) | 268(31.4) | 42(25.8) | 44(25.1) |  | 121(43.2) | 159(38.5) | 36(43.4) | 45(38.8) |  |
 College or above | 282(41.4) | 419(49.0) | 92(56.4) | 95(54.3) |  | 53(18.9) | 136(32.9) | 39(45.9) | 52(44.8) |  |
 Missing | 10(1.4) | 12(1.4) | 6(3.7) | 6(3.5) |  | 2(0.8) | 5(1.2) | 1(1.1) | 1(0.9) |  |
Income (1000 won/month) | Â | Â | Â | Â | 0.532 | Â | Â | Â | Â | 0.066 |
  < 2000 | 182(26.7) | 223(26.1) | 35(21.5) | 36(20.6) |  | 81(28.9) | 113(27.4) | 19(22.4) | 20(17.2) |  |
 2000–4000 | 284(41.6) | 363(42.5) | 67(41.1) | 73(41.7) |  | 115(41.1) | 159(38.5) | 33(38.8) | 45(38.8) |  |
  > 4000 | 178(26.1) | 231(27.0) | 51(31.3) | 53(30.3) |  | 63(22.5) | 118(28.6) | 25(29.4) | 43(37.1) |  |
 Missing | 38(5.6) | 38(4.4) | 10(6.1) | 13(7.4) |  | 21(7.5) | 23(5.5) | 8(9.4) | 8(6.9) |  |
Body mass index (kg/m2) | Â | Â | Â | Â | 0.294 | Â | Â | Â | Â | 0.852 |
  < 25 | 434(63.6) | 520(60.8) | 109(66.9) | 103(58.9) |  | 199(71.1) | 294(71.2) | 62(72.9) | 87(75.0) |  |
  ≥ 25 | 247(36.2) | 335(39.2) | 54(33.1) | 72(41.1) |  | 81(28.9) | 119(28.8) | 23(27.1) | 29(25.0) |  |
 Missing | 1(0.2) | 0(0.0) | 0(0.0) | 0(0.0) |  | 0(0.0) | 0(0.0) | 0(0.0) | 0(0.0) |  |
Smoking status | Â | Â | Â | Â | 0.207 | Â | Â | Â | Â | 0.194 |
 Non-smoker | 152(22.3) | 167(19.5) | 35(21.5) | 36(20.6) |  | 257(91.8) | 385(93.2) | 82(96.5) | 111(95.7) |  |
 Ex-smoker | 329(48.2) | 456(53.3) | 88(54.0) | 101(57.7) |  | 9(3.2) | 15(3.6) | 2(2.4) | 5(4.3) |  |
 Current smoker | 201(29.5) | 232(27.2) | 40(24.5) | 38(21.7) |  | 14(5.0) | 13(3.2) | 1(1.1) | 0(0.0) |  |
Alcohol consumption | Â | Â | Â | Â | 0.913 | Â | Â | Â | Â | 0.492 |
 Non-drinker | 117(17.2) | 135(15.8) | 24(14.7) | 30(17.1) |  | 161(57.5) | 253(61.2) | 51(60.0) | 69(59.5) |  |
 Ex-drinker | 80(11.7) | 117(13.7) | 20(12.3) | 22(12.6) |  | 17(6.1) | 30(7.3) | 8(9.4) | 4(3.4) |  |
 Current drinker | 485(71.1) | 603(70.5) | 119(73.0) | 123(70.3) |  | 102(36.4) | 130(31.5) | 26(30.6) | 43(37.1) |  |
Regular exercise | Â | Â | Â | Â | <.001 | Â | Â | Â | Â | <.001 |
 No | 359(52.6) | 396(46.3) | 69(42.3) | 53(30.3) |  | 184(65.7) | 218(52.8) | 45(52.9) | 40(34.5) |  |
 Yes | 309(45.3) | 433(50.6) | 92(56.4) | 119(68.0) |  | 96(34.3) | 194(47.0) | 40(47.1) | 76(65.5) |  |
 Missing | 14(2.1) | 26(3.0) | 2(1.2) | 3(1.7) |  | 0(0.0) | 1(0.2) | 0(0.0) | 0(0.0) |  |
First-degree family history of cancer | Â | Â | Â | Â | 0.309 | Â | Â | Â | Â | 0.283 |
 No | 407(59.7) | 473(55.3) | 92(56.4) | 106(60.6) |  | 141(50.4) | 231(55.9) | 51(60.0) | 59(50.9) |  |
 Yes | 275(40.3) | 379(44.3) | 71(43.6) | 68(38.9) |  | 139(49.6) | 182(44.1) | 34(40.0) | 57(49.1) |  |
 Missing | 0(0.0) | 3(0.4) | 0(0.0) | 1(0.5) |  | 0(0.0) | 0(0.0) | 0(0.0) | 0(0.0) |  |
First-degree family history of colorectal cancer | Â | Â | Â | Â | 0.363 | Â | Â | Â | Â | 0.402 |
 No | 634(93.0) | 795(93.0) | 151(92.6) | 168(96.0) |  | 265(94.6) | 379(91.8) | 81(95.3) | 107(92.2) |  |
 Yes | 48(7.0) | 57(6.7) | 12(7.4) | 6(3.4) |  | 15(5.4) | 34(8.2) | 4(4.7) | 9(7.8) |  |
 Missing | 0(0.0) | 3(0.3) | 0(0.0) | 1(0.6) |  | 0(0.0) | 0(0.0) | 0(0.0) | 0(0.0) |  |
Fruit and vegetable intake, g/d2 | 290.4 ± 191.3 | 325.6 ± 217.1 | 384.8 ± 223.5 | 418.6 ± 251.4 | <.001 | 383.1 ± 256.5 | 424.7 ± 265.5 | 476.3 ± 218.1 | 514.2 ± 280.0 | <.001 |
Red meat intake, g/d2 | 60.2 ± 40.5 | 62.9 ± 40.9 | 66.1 ± 38.5 | 56.1 ± 38.4 | 0.071 | 39.9 ± 25.0 | 44.9 ± 28.3 | 48.5 ± 34.4 | 37.4 ± 26.8 | 0.004 |
Energy intake, kcal/d2 | 1803.6 ± 543.5 | 1860.2 ± 555.8 | 1937.0 ± 596.8 | 2045.0 ± 621.7 | <.001 | 1597.4 ± 522.3 | 1633.4 ± 549.2 | 1840.8 ± 605.4 | 1885.5 ± 642.5 | <.001 |