Table 3.
Blood micronutrients in those who did and did not supplement with folic acid
| Circulating micronutrients | Daily folic acid intake | P value | ||
|---|---|---|---|---|
| No folic acid | 250–800 µg | >1000 µg | ||
| n | 27 | 67 | 41 | |
| Hcy µmol/L | 5.0 (4.5–5.4) | 4.7 (4.3–5.1) | 4.3 (3.8–4.7) | 0.177 |
| RBC folate nmol/L | 523 (423–622) | 613 (559–668) b | 800 (745–844) a | <0.001 |
| Serum folate nmol/L | 19.5 (15.7–23.3) | 25.9 (23.8–27.6) bc | 32.5 (30.0–35.5) a | <0.001 |
| Serum B12 pmol/L | 173 (134–212) | 215 (199–258) b | 315 (265–353) a | <0.001 |
| RBC B6%* | 51.5 (46.7–56.3) | 46.9 (44.3–49.7) b | 27.8 (23.2–33.4) a | <0.001 |
All data are represented as mean (95% confidence interval) calculated using one‐way analysis of variance. RBC, red blood cell. *Based on pyridoxal phosphate activation activity that is inversely related to vitamin B6 concentration. a P < 0.001 compared with no folic acid consumption; b P < 0.001 compared with folic acid consumption >1000 µg; c P < 0.005 compared with no folic acid consumption. Bold indicates P values that are significant (P < 0.050).