Table 1.
Baseline characteristics of study participants grouped by use of fish oil supplements
| Characteristics | All participants (n=415 737) |
Non-users of supplements (n=285 372) |
Users of supplements (n=130 365) |
| Age (years) | |||
| <65 | 346 524 (83.4) | 245 679 (86.1) | 100 845 (77.4) |
| ≥65 | 69 213 (16.6) | 39 693 (13.9) | 29 520 (22.6) |
| Sex | |||
| Women | 228 758 (55.0) | 153 715 (53.9) | 75 043 (57.6) |
| Men | 186 979 (45.0) | 131 657 (46.1) | 55 322 (42.4) |
| Ethnic group | |||
| White | 392 851 (94.5) | 268 845 (94.2) | 124 006 (95.1) |
| Non-white | 22 886 (5.5) | 16 527 (5.8) | 6359 (4.9) |
| Setting* | |||
| Rural | 57 474 (14.0) | 38 731 (13.7) | 18 743 (14.5) |
| Urban | 354 186 (86.0) | 243 654 (86.3) | 110 532 (85.5) |
| Body mass index* | |||
| Underweight | 2149 (0.5) | 1565 (0.6) | 584 (0.4) |
| Normal weight | 137 806 (33.3) | 92 895 (32.7) | 44 911 (34.6) |
| Overweight | 176 041 (42.6) | 119 539 (42.1) | 56 502 (43.5) |
| Obese | 97 774 (23.6) | 69 950 (24.6) | 27 824 (21.4) |
| Consumption of oily fish (times/week) | |||
| <2 | 343 096 (82.5) | 241 491 (84.6) | 101 605 (77.9) |
| ≥2 | 72 641 (17.5) | 43 881 (15.4) | 28 760 (22.1) |
| Consumption of non-oily fish (times/week) | |||
| <2 | 348 253 (83.8) | 241 331 (84.6) | 106 922 (82.0) |
| ≥2 | 67 484 (16.2) | 44 041 (15.4) | 23 443 (18.0) |
| Consumption of vegetables* (times/week) | |||
| <2 | 28 365 (6.8) | 21 963 (7.7) | 6402 (4.9) |
| 2-3 | 119 066 (28.7) | 84 866 (29.8) | 34 200 (26.3) |
| ≥4 | 267 926 (64.5) | 178 254 (62.5) | 89 672 (68.3) |
| Consumption of fruit* (times/week) | |||
| <2 | 115 111 (27.7) | 88 845 (31.2) | 26 266 (20.2) |
| 2-3 | 169 869 (40.9) | 116 655 (40.9) | 53 214 (40.8) |
| ≥4 | 130 467 (31.4) | 79 657 (27.9) | 50 810 (39.0) |
| Consumption of red meat* (times/week) | |||
| <2 | 61 945 (14.9) | 42 846 (15.0) | 19 099 (14.7) |
| 2-3 | 183 952 (44.3) | 122 621 (43.0) | 61 331 (47.1) |
| ≥4 | 169 588 (40.8) | 119 712 (42.0) | 49 876 (38.9) |
| Smoking status | |||
| Never | 233 367 (56.1) | 161 564 (56.6) | 71 803 (55.1) |
| Ever | 139 168 (33.5) | 91 189 (32.0) | 47 979 (36.8) |
| Current | 43 202 (10.4) | 32 619 (11.4) | 10 583 (8.1) |
| Consumption of alcohol | |||
| Never | 17 911 (4.3) | 12 982 (4.5) | 4929 (3.8) |
| Ever | 13 836 (3.3) | 9762 (3.4) | 4074 (3.1) |
| Current | 383 990 (92.4) | 262 628 (92.0) | 121 362 (93.1) |
| Physical activity* (%) | |||
| Low | 62 892 (18.5) | 46 526 (20.0) | 16 366 (15.4) |
| Moderate | 138 203 (40.8) | 95 958 (41.2) | 42 245 (39.8) |
| High | 137 878 (40.7) | 90 241 (38.8) | 47 637 (44.8) |
| Townsend deprivation index (mean, SD) | −1.4 (3.1) | −1.3 (3.0) | −1.5 (3.0) |
Data are number (%) unless stated otherwise.
*These variables included missing values.