TABLE 1.
Characteristics of healthy, premenopausal women participating in the BioCycle Study by tertile of mean serum concentrations of retinol, ascorbic acid, and α-tocopherol across the study1
| Tertiles of mean retinol, μg/dL |
Tertiles of mean ascorbic acid, mg/dL |
Tertiles of mean α-tocopherol, μg/dL |
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| Total cohort | Low(0.22–0.34) | Medium (>0.34 to 0.40) | High(>0.40 to 0.65) | P2 | Low(0.70–1.54) | Medium (>1.54 to 1.85) | High(>1.85 to 4.22) | P2 | Low(3.68–7.33) | Medium (>7.33 to 8.75) | High(>8.75 to 28.77) | P2 | |
| Women, n | 254 | 84 | 85 | 85 | 86 | 83 | 85 | 84 | 85 | 85 | |||
| Age, y | 27.3 ± 8.2 | 27.5 ± 8.4 | 26.7 ± 7.6 | 27.7 ± 8.7 | 0.69 | 27.5 ± 8.1 | 26.1 ± 7.7 | 28.4 ± 8.7 | 0.19 | 23.7 ± 6.3c | 26.9 ± 7.7b | 31.3 ± 8.7a | <0.001 |
| BMI, kg/m2 | 24.1 ± 3.9 | 24.1 ± 4.1 | 23.7 ± 3.4 | 24.5 ± 4.0 | 0.42 | 25.4 ± 4.1a | 24.0 ± 3.8b | 22.8 ± 3.2b | <0.001 | 24.0 ± 3.9 | 23.8 ± 3.8 | 24.5 ± 3.9 | 0.60 |
| Energy intake, kcal/d | 1610 ± 37 | 1520 ± 376b | 1650 ± 373a,b | 1660 ± 370a | 0.02 | 1590 ± 401 | 1630 ± 342 | 1620 ± 388 | 0.77 | 1560 ± 332 | 1600 ± 361 | 1670 ± 410 | 0.19 |
| Race | <0.001 | 0.16 | <0.001 | ||||||||||
| White | 152 (60) | 36 (43) | 55 (65) | 61 (72) | 52 (61) | 53 (64) | 47 (55) | 34 (40) | 56 (66) | 62 (73) | |||
| Black | 50 (20) | 30 (36) | 10 (12) | 10 (12) | 20 (23) | 17 (20) | 13 (15) | 26 (31) | 12 (14) | 12 (14) | |||
| Other | 52 (20) | 18 (21) | 20 (23) | 14 (16) | 14 (16) | 13 (16) | 25 (29) | 24 (29) | 17 (20) | 11 (13) | |||
| ≤High school education | 33 (13) | 12 (14) | 8 (9) | 13 (15) | 0.47 | 11 (13) | 15 (18) | 7 (8) | 0.17 | 11 (13) | 12 (14) | 10 (12) | 0.92 |
| Married | 65 (26) | 16 (19) | 21 (25) | 28 (33) | 0.12 | 17 (20) | 21 (25) | 27 (32) | 0.21 | 5 (6) | 27 (32) | 33 (39) | <0.001 |
| Nulliparous3 | 183 (72) | 61 (73) | 64 (75) | 58 (68) | 0.79 | 62 (72) | 62 (75) | 59 (69) | 0.70 | 73 (87) | 61 (72) | 49 (58) | <0.001 |
| Current smoker | 10 (4) | 1 (1) | 5 (6) | 4 (5) | 0.36 | 4 (5) | 4 (5) | 2 (2) | 0.72 | 4 (5) | 0 (0) | 6 (7) | 0.03 |
| Physical activity | 0.40 | 0.47 | 0.80 | ||||||||||
| Low | 25 (10) | 10 (12) | 9 (11) | 6 (7) | 6 (7) | 9 (11) | 10 (12) | 10 (12) | 8 (9) | 7 (8) | |||
| Moderate | 91 (36) | 30 (36) | 35 (41) | 26 (31) | 30 (35) | 26 (31) | 35 (41) | 27 (32) | 34 (40) | 30 (35) | |||
| High | 138 (54) | 44 (52) | 41 (48) | 53 (62) | 50 (58) | 48 (58) | 40 (47) | 47 (56) | 43 (51) | 48 (56) | |||
| Past OC use3 | 138 (54) | 44 (52) | 49 (58) | 45 (53) | 0.90 | 53 (62) | 41 (49) | 44 (52) | 0.49 | 34 (40) | 49 (58) | 55 (65) | 0.01 |
| Serum biomarkers | |||||||||||||
| Total cholesterol, mg/dL | 165 ± 27.3 | 163 ± 28.8 | 161 ± 25.1 | 169 ± 27.6 | 0.15 | 158 ± 25.1b | 167 ± 27.6a,b | 169 ± 28.2a | 0.02 | 145 ± 17.4c | 165 ± 19.6b | 183 ± 29.0a | <0.001 |
| F2-isoprostane, pg/mL | 52.9 ± 22.2 | 51.1 ± 20.0 | 52.6 ± 24.4 | 54.8 ± 22.2 | 0.55 | 59.6 ± 26.0a | 53.4 ± 22.9a | 45.5 ± 13.8b | <0.001 | 57.5 ± 28.6 | 50.0 ± 16.3 | 51.2 ± 19.6 | 0.06 |
| Retinol, μg/mL | 0.38 ± 0.08 | 0.30 ± 0.03c | 0.37 ± 0.02b | 0.46 ± 0.06a | <0.001 | 0.37 ± 0.08 | 0.38 ± 0.08 | 0.38 ± 0.08 | 0.25 | 0.35 ± 0.06c | 0.38 ± 0.06b | 0.41 ± 0.09a | <0.001 |
| Ascorbic acid, mg/dL | 1.77 ± 0.48 | 1.70 ± 0.46 | 1.77 ± 0.45 | 1.84 ± 0.51 | 0.18 | 1.33 ± 0.17c | 1.71 ± 0.08b | 2.28 ± 0.43a | <0.001 | 1.59 ± 0.37b | 1.81 ± 0.46a | 1.91 ± 0.54a | <0.001 |
| α-Tocopherol, μg/mL | 8.25 ± 2.19 | 7.80 ± 1.70b | 7.95 ± 1.74b | 8.98 ± 2.78a | <0.001 | 7.79 ± 2.76b | 8.27 ± 1.67a,b | 8.69 ± 1.89a | 0.03 | 6.35 ± 0.72c | 8.00 ± 0.41b | 10.4 ± 2.35a | <0.001 |
| γ-Tocopherol, μg/mL | 1.80 ± 0.57 | 1.75 ± 0.53b | 1.70 ± 0.51b | 1.95 ± 0.64a | 0.01 | 1.84 ± 0.54 | 1.83 ± 0.53 | 1.73 ± 0.64 | 0.41 | 1.64 ± 0.48b | 1.82 ± 0.54a,b | 1.94 ± 0.65a | 0.01 |
| Lutein, μg/mL | 0.12 ± 0.05 | 0.12 ± 0.04 | 0.12 ± 0.04 | 0.13 ± 0.06 | 0.17 | 0.10 ± 0.04c | 0.12 ± 0.03b | 0.15 ± 0.05a | <0.001 | 0.11 ± 0.04b | 0.12 ± 0.04a,b | 0.14 ± 0.06a | <0.001 |
| Lycopene, μg/mL | 0.46 ± 0.16 | 0.47 ± 0.17 | 0.45 ± 0.15 | 0.48 ± 0.16 | 0.42 | 0.40 ± 0.13b | 0.47 ± 0.14b | 0.52 ± 0.18a | <0.001 | 0.42 ± 0.17b | 0.46 ± 0.13b | 0.52 ± 0.16a | <0.001 |
| β-carotene, μg/mL | 0.20 ± 0.12 | 0.19 ± 0.13 | 0.21 ± 0.13 | 0.19 ± 0.11 | 0.24 | 0.13 ± 0.07c | 0.17 ± 0.07b | 0.30 ± 0.15a | <0.001 | 0.15 ± 0.09b | 0.21 ± 0.13a | 0.23 ± 0.13a | <0.001 |
1
Values are means ± SDs or n (%) as indicated. Labeled means without a common letter differ, P < 0.05 (adjusted for multiple comparisons). OC, oral contraceptives.
2
Two-sided P values for continuous variables were calculated with ANOVA and for categorical variables with Fisher’s exact test.
3
Five women were missing alpha serum Vitamin E concentrations on all visits, 6 women were missing information on parity, and 4 were missing information on past OC use.