TABLE 2.
Serum ferritin concentrations according to categories of food intake1
| Men | Women | |||||
| n | Mean, ng/mL | Multivariable-adjusted mean (95% CI), ng/mL | n | Mean, ng/mL | Multivariable-adjusted mean (95% CI), ng/mL | |
| Red meat | ||||||
| Quartile 1 | 801 | 115.4 | 116.2 (107.7, 125.3) | 876 | 38.0 | 39.6 (36.6, 42.8) |
| Quartile 2 | 850 | 127.5 | 129.0 (120.0, 138.6) | 1026 | 35.9 | 38.3 (35.7, 41.1) |
| Quartile 3 | 785 | 134.5 | 137.5 (127.5, 148.3) | 932 | 38.9 | 40.6 (37.7, 43.7) |
| Quartile 4 | 806 | 135.6 | 137.2 (127.0, 148.3) | 887 | 39.6 | 43.5 (40.2, 47.0) |
| P-trend | <0.001 | 0.002 | 0.17 | 0.03 | ||
| Grains | ||||||
| Quartile 1 | 793 | 136.1 | 137.0 (126.9, 147.9) | 966 | 36.6 | 39.6 (36.8, 42.7) |
| Quartile 2 | 815 | 129.8 | 131.9 (122.5, 141.9) | 1002 | 39.9 | 41.2 (38.4, 44.2) |
| Quartile 3 | 807 | 123.8 | 123.7 (114.8, 133.2) | 915 | 39.3 | 41.1 (38.2, 44.2) |
| Quartile 4 | 827 | 122.9 | 123.9 (114.5, 134.1) | 838 | 36.1 | 39.3 (36.1, 42.8) |
| P-trend | 0.03 | 0.05 | 0.52 | 0.77 | ||
| Pork | ||||||
| Quartile 1 | 828 | 117.9 | 119.0 (110.4, 128.2) | 921 | 37.8 | 39.8 (36.8, 42.9) |
| Quartile 2 | 783 | 124.8 | 125.6 (116.6, 135.2) | 980 | 36.4 | 39.3 (36.6, 42.2) |
| Quartile 3 | 822 | 135.8 | 139.0 (129.0, 149.7) | 904 | 38.2 | 40.3 (37.4, 43.4) |
| Quartile 4 | 809 | 134.2 | 136.4 (126.2, 147.4) | 916 | 39.8 | 42.4 (39.3, 45.8) |
| P-trend | 0.005 | 0.006 | 0.17 | 0.14 | ||
| Vegetables | ||||||
| Quartile 1 | 797 | 133.1 | 131.2 (121.8, 141.3) | 950 | 34.6 | 39.5 (36.7, 42.5) |
| Quartile 2 | 825 | 134.1 | 134.1 (124.7, 144.1) | 945 | 36.5 | 39.6 (36.8, 42.6) |
| Quartile 3 | 808 | 127.0 | 129.1 (119.8, 139.1) | 938 | 41.2 | 43.4 (40.4, 46.6) |
| Quartile 4 | 812 | 118.2 | 121.8 (112.7, 131.5) | 888 | 40.3 | 38.9 (36.0, 42.1) |
| P-trend | 0.006 | 0.09 | <0.001 | 0.97 | ||
| Fish, g/d | ||||||
| 0 | 1783 | 124.4 | 124.7 (118.0, 131.7) | 2133 | 37.6 | 39.9 (37.7, 42.1) |
| >0–60 | 511 | 134.3 | 136.3 (124.6, 149.1) | 694 | 36.8 | 40.2 (37.0, 43.6) |
| >60 | 948 | 131.5 | 134.6 (125.5, 144.4) | 894 | 40.0 | 41.6 (38.6, 44.8) |
| P-trend | 0.17 | 0.06 | 0.17 | 0.30 | ||
| Poultry, g/d | ||||||
| 0 | 2350 | 121.9 | 123.9 (117.8, 130.2) | 2772 | 38.9 | 40.7 (38.7, 42.9) |
| >0–15 | 26 | 169.2 | 171.3 (118.5, 247.7) | 37 | 32.6 | 37.0 (26.8, 51.1) |
| >15 | 866 | 144.7 | 143.7 (133.6, 154.5) | 912 | 35.5 | 39.6 (36.8, 42.6) |
| P-trend | <0.001 | <0.001 | 0.03 | 0.49 | ||
| Eggs, g/d | ||||||
| 0 | 1100 | 124.9 | 127.5 (119.1, 136.4) | 1242 | 38.8 | 39.1 (36.5, 41.9) |
| >0–40 | 1588 | 130.8 | 131.6 (124.4, 139.3) | 1919 | 37.2 | 40.2 (38.0, 42.5) |
| >40 | 554 | 126.1 | 125.8 (115.4, 137.2) | 560 | 38.9 | 43.2 (39.5, 47.2) |
| P-trend | 0.85 | 0.79 | 0.98 | 0.06 | ||
| Tubers, g/d | ||||||
| 0 | 1878 | 129.9 | 130.4 (123.3, 138.0) | 2152 | 38.0 | 39.2 (37.1, 41.5) |
| >0–60 | 524 | 133.6 | 135.7 (124.3, 148.1) | 680 | 36.1 | 39.7 (36.6, 43.1) |
| >60 | 840 | 120.5 | 122.4 (113.5, 132.0) | 889 | 39.6 | 44.0 (40.7, 47.6) |
| P-trend | 0.07 | 0.14 | 0.36 | 0.009 | ||
| Fruits, g/d | ||||||
| 0 | 2246 | 127.5 | 127.0 (120.5, 133.8) | 2297 | 37.9 | 39.6 (37.5, 41.9) |
| >0–80 | 290 | 150.4 | 154.4 (137.6, 173.4) | 346 | 41.9 | 44.3 (39.7, 49.5) |
| >80 | 706 | 121.3 | 126.9 (117.4, 137.3) | 1078 | 36.9 | 40.5 (37.8, 43.4) |
| P-trend | 0.29 | 0.96 | 0.49 | 0.61 | ||
| Milk, g/d | ||||||
| 0 | 3034 | 128.7 | 129.4 (123.4, 135.7) | 3410 | 37.8 | 40.3 (38.4, 42.4) |
| >0 | 208 | 118.0 | 127.4 (110.8, 146.4) | 311 | 39.9 | 40.7 (36.1, 45.9) |
| P-trend | 0.22 | 0.83 | 0.42 | 0.88 | ||
All the mean values are the geometric mean of ferritin concentration. The medians for quartiles of food intake (men/women) were as follows—red meat: 0/0, 50.0/35.0, 96.1/76.7, and 168.1/143.1 g/d; grains: 283.3/233.3, 383.3/316.7, 476.4/400.0, and 650.0/564.0 g/d; vegetables: 170.0/160.0, 283.3/266.7, 383.3/363.3, and 541.7/516.4 g/d; and pork: 0/0, 43.3/33.3, 83.3/70.0, and 160.0/133.3 g/d. The general linear model was adjusted for total energy intake, age, annual income level, moderate-to-vigorous physical activity time, BMI, alcohol intake, tea consumption, and serum high-sensitivity C-reactive protein concentration as continuous variables and educational status, place of residence, geographic region, and smoking status as categorical variables except the stratification variable.