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Updated: Jun 25, 2026

Modifying Levels of Maternal Dietary Folic Acid or Choline to Study the Impact of Deficiencies on Offspring Health Outcomes
Published on: June 28, 2024
Effect of 2 pieces of nutritional advice on folate status in Swedish women: a randomized controlled trial
Veronica E Ohrvik1, Johan C Olsson, Birgitta E Sundberg
1Department of Food Science, Swedish University of Agricultural Sciences, Uppsala, Sweden. veronica.ohrvik@lmv.slu.se
Background:
Ten years after the introduction of mandatory folic acid fortification in the United States, Canada, and Costa Rica, the issue is still under debate in several countries, and Sweden recently decided against mandatory fortification.
Objective:
The objective was to determine the folate status of women after an intervention involving 2 Swedish dietary recommendations: a food recommendation (bread) and a complete meal recommendation (breakfast).
Design:
Fifty-one free-living women with normal folate status participated in a 12-wk controlled intervention trial. Subjects were randomly assigned to one of the following interventions: apple juice (control group; n = 17), a breakfast providing 125 microg folate (breakfast group; n = 17), or 5 slices of whole-meal bread to be eaten over the course of the day, which provided 70 microg folate (bread group; n = 17). Folate status was assessed on the basis of concentrations of erythrocyte folate, serum folate, and plasma total homocysteine (tHcy) at baseline and at weeks 8 and 12 of the trial.
Results:
In the breakfast group, initial median concentrations of erythrocyte folate (805 nmol/L) increased by 172 nmol/L (95% CI: 24, 293; P = 0.02) relative to the control. The relative increase in initial serum folate (2 nmol/L, 95% CI: 0, 5; P = 0.06) was nonsignificant. The initial tHcy concentration (8.7 micromol/L) decreased by 2.3 micromol/L (95% CI: -1, -3.4; P < 0.01). In the bread group, the initial tHcy concentration (9.1 micromol/L) decreased nonsignificantly by 1.4 micromol/L (95% CI: 0, -2.8; P = 0.08) relative to the control group, whereas other outcomes were stable.
Conclusions:
The folate status of the subjects improved after regular consumption of the breakfast meal. The additional folate intake from the bread maintained the folate status but was not sufficient to improve it.
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