TABLE 2.
Folic acid intake from different sources by variable categories and stratified by folic acid–containing dietary supplement use in the US population ≥1 y of age, NHANES 2007–20081
| Nonusers | Users |
|||
| Variables | Diet, μg/d | Diet, μg/d | Supplements, μg/d | Total, μg/d |
| All | 145 (137, 156) | 135 (126, 148) | 400 (379, 400) | 508 (482, 539) |
| Age, y | ||||
| 1–5 | 126 (103, 149) | 86.2 (62.5, 121)* | 198 (181, 262) | 345 (306, 389) |
| 6–11 | 183 (157, 218) | 141 (115, 206) | 183 (138, 259) | 373 (320, 458) |
| 12–19 | 161 (145, 200) | 187 (97.3, 279) | 159 (106, 389) | 479 (282, 602) |
| 20–39 | 137 (121, 167) | 149 (126, 195) | 325 (266, 381) | 490 (436, 592) |
| 40–59 | 146 (130, 168) | 135 (96.7, 178) | 385 (380, 390) | 542 (479, 597) |
| ≥60 | 127 (104, 144) | 126 (101, 165) | 400 (400, 400) | 589 (534, 626) |
| P value | <0.0001 | 0.0069 | <0.0001 | <0.0001 |
| P value adjusted | <0.0001 | 0.0414 | <0.0001 | 0.0018 |
| Sex | ||||
| Male | 170 (154, 181) | 164 (142, 181) | 390 (325, 392) | 497 (474, 547) |
| Female | 128 (117, 140) | 116 (91.4, 137) | 400 (400, 400) | 515 (481, 550) |
| P value | <0.0001 | 0.0108 | 0.0029 | 0.20 |
| P value adjusted | <0.0001 | 0.0058 | 0.0429 | 0.50 |
| Race-ethnicity2 | ||||
| All Hispanic | 146 (134, 163) | 152 (124, 203) | 283 (222, 391) | 491 (407, 576) |
| MA | 133 (115, 161) | 143 (109, 207) | 254 (174, 391) | 451 (356, 602) |
| NHB | 125 (115, 135) | 112 (89.3, 135) | 267 (201, 354) | 423 (374, 461) |
| NHW | 145 (133, 160) | 135 (122, 155) | 400 (400, 400) | 520 (484, 562) |
| P value | 0.0165 | 0.0230 | 0.0013 | 0.0003 |
| P value adjusted | 0.0361 | 0.10 | 0.0108 | 0.0065 |
| Fasting time, h | ||||
| <3 | 166 (140, 179) | 127 (107, 162)* | 390 (270, 393) | 479 (436, 528) |
| 3 to <8 | 145 (130, 160) | 113 (82.3, 180) | 383 (367, 393) | 540 (499, 605) |
| ≥8 | 141 (129, 152) | 148 (135, 170) | 400 (348, 400) | 536 (484, 588) |
| P value | 0.0036 | 0.19 | 0.10 | 0.15 |
| P value adjusted | 0.0019 | 0.15 | 0.38 | 0.60 |
Values are weighted medians (95% CIs). “Diet” represents information from first 24-h dietary recall. “Supplements” represents mean daily use during the past 30 d. For sample sizes, see Supplemental Table 2. Pregnant and lactating women were excluded; otherwise pairwise deletion was used for missing data. P values [with and without controlling for additional covariates (age, sex, race-ethnicity, and fasting time)] are for comparison of geometric means (not medians) and are based on the Wald F test, which tests whether at least 1 of the means across the categories is significantly different. *Significant difference in dietary folic acid intake between users and nonusers of folic acid–containing dietary supplements, P < 0.05. MA, Mexican American; NHB, non-Hispanic black; NHW, non-Hispanic white.
All Hispanic subgroup represents the sum of MA and other Hispanic (not shown) ethnicity. P value represents the comparison of all Hispanic, NHB, NHW, and other (not shown).