Folate status in the US population 20 y after the introduction of folic acid fortification

Abstract

Background Enriched cereal-grain products have been fortified in the United States for >20 y to improve folate status in women of reproductive age and reduce the risk of folic acid–responsive neural tube birth defects (NTDs). Objectives Our objectives were to assess postfortification changes in folate status in the overall US population and in women aged 12–49 y and to characterize recent folate status by demographic group and use of folic acid–containing supplements. Methods We examined cross-sectional serum and RBC folate data from the NHANES 1999–2016. Results Serum folate geometric means increased from 2007–2010 to 2011–2016 in persons aged ≥1 y (38.7 compared with 40.6 nmol/L) and in women (35.3 compared with 37.0 nmol/L), whereas RBC folate showed no significant change. Younger age groups, men, and Hispanic persons showed increased serum and RBC folate concentrations, whereas non-Hispanic black persons and supplement nonusers showed increased serum folate concentrations. The folate insufficiency prevalence (RBC folate <748 nmol/L; NTD risk) in women decreased from 2007–2010 (23.2%) to 2011–2016 (18.6%) overall and in some subgroups (e.g., women aged 20–39 y, Hispanic and non-Hispanic black women, and supplement nonusers). After covariate adjustment, RBC folate was significantly lower in all age groups (by ∼10–20%) compared with persons aged ≥60 y and in Hispanic (by 8.2%), non-Hispanic Asian (by 12.1%), and non-Hispanic black (by 20.5%) compared with non-Hispanic white women (2011–2016). The 90th percentile for serum (∼70 nmol/L) and RBC (∼1800 nmol/L) folate in supplement nonusers aged ≥60 y was similar to the geometric mean in users (2011–2014). Conclusions Blood folate concentrations in the US population overall and in women have not decreased recently, and folate insufficiency rates are ∼20%. Continued monitoring of all age groups is advisable given the high folate status particularly in older supplement users.

Inadequate Status and Low Awareness of Folate in Switzerland—A Call to Strengthen Public Health Measures to Ensure Sufficient Intakes

“…In our study, the prevalence of folate insufficiency was highest in the first trimester, decreasing throughout pregnancy and the late start of folate supplementation may explain the discrepancy with previously reported postpartum folate status. Lower prevalence of folate insufficiency (assay-specific cut-off of <748 nmol/L, which is equivalent to the WHO cut-off of 906 nmol/L) of 18.6% has been reported in 12-49-year-old women in the US [27], where mandatory folate fortification of enriched cereal grain products has been in place since 1998 [28]. A German study conducted between 2008 and 2011 reported that 86% of the adult population, and 88.2% of the female population, was sufficiently supplied with folate [29].…”

The Folate Concentration and/or Folic Acid Metabolites in Plasma as Factor for COVID-19 Infection

“…Plasma and red blood cell (RBC) concentration also depends on the person’s ethnical group. For example, Non-Hispanic whites possess a 1,180 nmol/L RBC concentration in contrast to Non-Hispanic African Americans who have a 906 nmol/L ( Pfeiffer et al., 2019 ). On the other hand, pregnant women who were taking 400 mcg of FA per day can reach a concentration of 2,862 nmol/L in RBC at delivery ( Plumptre et al., 2015 ).…”

Modeling shows high potential of folic acid‐fortified salt to accelerate global prevention of major neural tube defects

“…Fortification has been shown, through nationally representative dietary surveys, to relate to a consumption of about one‐third the RDA of synthetic folic acid from required fortification in “enriched” cereal grains (Yang et al, 2010). This intervention has not only resulted in a consistent improvements the mean blood folate concentrations among women of reproductive age to levels adequate enough to prevent FAP SBA (Pfeiffer et al, 2019), but also a significant reduction in the prevalence of FAP SBA, as shown through robust postfortification birth defects surveillance data nationally (Williams et al, 2015). Similar effect has been noted in Canada (De Wals et al, 2008).…”