Review Article

Folate Intake and Markers of Folate Status in Women of Reproductive Age, Pregnant and Lactating Women: A Meta-Analysis

Table 6

Forest plot of the effects of total folate supply (i.e., supplement plus dietary folate), with the supplement provided in form of folic acid and [ 6 S ]-5-methyltetrahydrofolate (5-MTHF) on plasma homocysteine (tHcy) folate in childbearing age, pregnant and lactating women.

Study or subgroupBetaSEWeightBeta
IV, random, 95% CI
Beta
IV, random, 95% CI

Folic acid470656.fig.004
 Adank et al., 2003 [24]−0.121659950.0518569911.9%−0.12 [−0.22, −0.02]
 Brouwer et al., 1999_2 [25]−0.129397360.032180814.7%−0.13 [−0.19, −0.07]
 Daly et al., 2002 [29]−0.071606390.0542243211.5%−0.07 [−0.18, 0.03]
 Ellison et al., 2004 [33]−0.417482870.085650777.7%−0.42 [−0.59, −0.25]
 Fohr et al., 2002 a [31]−0.120811280.0308007514.9%−0.12 [−0.18, −0.06]
 Green et al., 2005 [32]−0.157125230.166963333.0%−0.16 [−0.48, 0.17]
 Houghton et al., 2006 f [36]0.026530850.0464580712.7%0.03 [−0.06, 0.12]
 Lamers et al., 2004 n [30]−0.116733330.0404207513.5%−0.12 [−0.20, −0.04]
 Mackey and Picciano, 1999 [20]0.051497420.0649078410.1%0.05 [−0.08, 0.18]
Subtotal (95% CI)100.0%−0.10 [−0.17, −0.04]
Heterogeneity: Tau2 = 0.01; Chi2 = 28.61, df = 8 ( 𝑃 = 0 . 0 0 0 4 ); 𝐼 2 = 72%
Test for overall effect: 𝑍 = 3.26 ( 𝑃 = 0 . 0 0 1 )
5-MTHF
 Fohr et al., 2002 b [31]−0.013274710.0395955537.5%−0.01 [−0.09, 0.06]
 Houghton et al., 2006 g [36]−0.036829170.0682317728.5%−0.04 [−0.17, 0.10]
 Lamers et al., 2004 p [30] −0.193166840.050691134.0%−0.19 [−0.29, −0.09]
Subtotal (95% CI) 100.0%−0.08 [−0.20, 0.04]
Heterogeneity: Tau2 = 0.01; Chi2 = 8.18, df =2 ( 𝑃 = 0 . 0 2 ); 𝐼 2 = 7 6 %
Test for overall effect: Z = 1.34 ( 𝑃 = 0 . 1 8 )