FA-fortified iodized salt improves folate status of nonpregnant women

Folic acid (FA) fortification of iodized salt results in improvements in women’s folate status, which then lowers the risk of neural tube defect (NTD)-affected pregnancies, a study has shown.

Nonpregnant Ethiopian women aged 18‒49 years (n=360) were included in this community-based, three-arm, household-randomized dose-response trial. Salts containing 32 parts per million (ppm) iodine and 99, 36, or 0 ppm FA were delivered to households biweekly for 26 weeks.

The investigators measured the participants’ fasting red blood cell (RBC) folate, serum folate, homocysteine, thyroglobulin, vitamin B12 biomarkers, glucose, and insulin, and urinary iodine/creatinine ratios before and during the intervention. They also measured salt intakes using weighed food records and recorded adverse events.

At baseline, the overall median RBC folate concentration was 476 nmol/L. The mean usual intakes of study salts (7.6 g/day) did not significantly differ across groups (p=0.58). The final median RBC folate concentrations were 1,275 nmol/L in the 99-ppm group, 1,004 nmol/L in the 36-ppm group, and 468 nmol/L in the 0-ppm group (all significantly different; p<0.001).

Furthermore, urinary iodine/creatinine ratios, serum thyroglobulin, insulin resistance, or reported adverse events did not differ across groups.

“FA fortification of cereal grains reduces the prevalence of folate insufficiency among adult females and related NTDs in their offspring,” the investigators said. “However, fortifiable cereal grains have limited reach in many lower-income countries, so additional fortification options need to be developed and evaluated.”