Table 2.
Predictors of serum folate and vitamin D levels.
| Predictors of serum folate levels | ||
| Median folate level (IQR), ng/ml | p value | |
| Smoking history | 0.046 | |
| Never | 14.0 (11.1 – 21.4) | |
| Former | 10.6 (8.1 – 16.2) | |
| Current | 11.0 (8.5 – 15.8) | |
| Sex | 0.52 | |
| Female | 14.1 (9.1 – 19.4) | |
| Male | 12.2 (10.3 – 15.2) | |
| Education | 0.25 | |
| Less than college graduate | 12.1 (8.7–16.2) | |
| College graduate or higher | 14.1 (9.7–18.9) | |
| Race/ethnicity | 0.88 | |
| Caucasian | 12.8 (9.6 – 17.3) | |
| Non-Caucasian | 12.4 (6.9 – 27.6) | |
| Age | 0.75 | |
| <30 y | 12.8 (10.3–16.2) | |
| ≥30 y | 13.0 (9.1–19.4) | |
| Season | 0.88 | |
| Winter | 12.9 (9.6 – 19.4) | |
| Spring | 15.2 (8.3 – 21.4) | |
| Summer | 12.2 (8.8 – 17.0) | |
| Fall | 13.0 (9.3 – 17.3) | |
| Vitamin D category | 0.38 | |
| <20 ng/ml | 11.9 (7.9 – 15.8) | |
| ≥20–29 ng/ml | 13.0 (10.3 – 23.0) | |
| ≥30 ng/ml | 13.4 (9.6 – 19.0) | |
| Predictors of serum vitamin D level | ||
| Median vitamin D level (IQR) | p value | |
| Smoking history | 0.31 | |
| Never | 23.5 (17 – 33) | |
| Former | 22.5 (15 – 32.5) | |
| Current | 26.5 (23 – 36) | |
| Sex | 0.0006 | |
| Female | 30 (22 – 36) | |
| Male | 20 (16 – 26) | |
| Education | 0.75 | |
| Less than college graduate | 25 (20– 33) | |
| College graduate or higher | 24 (17 – 36) | |
| Race/ethnicity | 0.09 | |
| Caucasian | 25 (18 – 33) | |
| Non-Caucasian | 18 (14 – 31) | |
| Age | 0.33 | |
| <30 | 27 (17–35) | |
| ≥ 30 | 23 (18–31) | |
| Season | 0.003 | |
| Winter | 20 (16 – 26) | |
| Spring | 17 (14 – 24) | |
| Summer | 27.5 (22 – 37) | |
| Fall | 28.5 (18 – 33) | |
| Folate tertile | 0.76 | |
| 1 (2.5 – 10.5 ng/ml) | 25 (17 – 33) | |
| 2 (10.5 – 16.2 ng/ml) | 24 (17 – 32) | |
| 3 (16.2 – 78.4 ng/ml) | 24 (21 – 32) | |