Background:Neural tube defects (NTDs) are serious birth defects that occur in the first month post-conception. Mandatory folic acid fortification of enriched grain products has reduced NTD prevalence in several countries. We examined the potential of salt as another vehicle for folic acid fortification.

Objective:To examine the change in serum folate concentration after one-month consumption of fortified iodized salt with folic acid (FISFA) among non-pregnant women of reproductive age. Secondary objectives: 1)feasibility of implementing FISFA intervention, and 2)acceptability of FISFA.

Methods:We conducted a pre-post intervention study (January-April 2023). Non-pregnant, 18-40-year-old women who lived alone/with a partner in Southern USA were consented. Participants received a FISFA saltshaker with the study salt (1g of sodium chloride salt fortified with 100mcg of folic acid) to use instead of regular table salt for one month. Serum folate was measured via immunoassay at baseline and one-month endpoint. Change in serum folate was assessed using a two-tailed Wilcoxon Signed Rank test for paired-samples.

Results:32 eligible women consented: 11 non-Hispanic-White, 11 non-Hispanic-Black, and 10-Hispanic. Post-intervention, there was a significant increase in median serum folate concentration of 1.40nmol/L (IQR0.74-2.05; p<0.001) from 24.08nmol/L to 25.96nmol/L in an analytical sample of n=29. An increase was seen in 28/29(93%) participants. Feasibility: 100% study consent and compliance. FISFA acceptability: 25 days average intake; 1.28g mean daily intake; 96.7% and 90% reported taste and color of FISFA as highly acceptable, respectively.

Conclusions:FISFA is an effective approach to increasing serum folate concentrations among women of childbearing age. Findings should be replicated in a larger study.