Folic Acid Fortification Increases Red Blood Cell Folate Concentrations in the Framingham Study

Abstract

In 1996 the Food and Drug Administration (FDA) issued a regulation to take effect in January 1998 that all enriched cereal grain products include 140 microg of folic acid/100 g. The present cross-sectional study was undertaken to assess the effect of this fortification on RBC folate concentrations in the Framingham Offspring Cohort. Among those who did not take B-vitamin supplements, we compared RBC folate in 561 individuals who were examined before implementation of the FDA mandatory folic acid fortification (not exposed) vs. 354 individuals who were examined after implementation of fortification (exposed). We calculated the prevalence of deficient (<160 microg/L, 362.6 nmol/L) and acceptable (>200 microg/L, 453.2 nmol/L) RBC folate concentrations in both groups. Those exposed to folic acid fortification had a mean RBC folate of 450.0 microg/L (1019.7 nmol/L), a value 38% higher than the mean RBC folate of 325.3 microg/L (737.1 nmol/L) in those who were not exposed to fortification (P < 0.001). The prevalence of individuals with deficient RBC folate was 4.9% in the group not exposed to fortification compared with 1.9% in the group exposed to fortification (P < 0.02), and the prevalence of individuals with acceptable RBC folate was 87.0% in the group not exposed to fortification compared with 96.1% in the group exposed to fortification (P < 0.001). Similar results were seen in individuals who used supplements containing B-vitamins. The results of this study showed that in this cohort, the introduction of folic acid fortification significantly improved folate nutritional status measured as RBC folate.

Folate intake estimated with an updated database and its association to blood folate and homocysteine in Korean college students

“…However, the mean erythrocyte folate concentrations of our subjects were much higher than the data from NHANES III (Ganji & Kafai, 2003), whereas the values were comparable with those in other studies carried out in USA and Canada prior to fortification as well as in Denmark and Korea where not exposed to fortification (House et al, 2000;Rasmussen et al, 2000;Choumenkovitch et al, 2001;Ahn et al, 2002). Homocysteine concentrations in our study were lower than those reported in UK, Canada, Netherlands and USA, (Bates et al, 1997;Ray et al, 2000;de Bree et al, 2001;Jacques et al, 2001), but were similar to the values (6.4-7.6 mmol/l) reported in Korea by other investigators (Lee et al, 1998(Lee et al, , 2000.…”

“…This was followed in Canada and Chile. In these countries, folic acid fortification resulted in the increase in folate consumption and circulating folate concentration in the general population, and the reduction of neural-tube defects (Jacques et al, 1999b;Choumenkovitch et al, 2001;Green, 2002;Ray et al, 2002;Hertrampf et al, 2003;Quinlivan & Gregory, 2003). There are still concerns about possible adverse effects such as masking symptoms of vitamin B 12 deficiency among those who consume synthetic folic acid in excess of the Tolerable Upper Intake level of 1.0 mg per day (Rader 2002;Rampersaud et al, 2003;Shane, 2003).…”

Relative influence of diet and physical activity on cardiovascular risk factors in urban Chinese adults

“…This finding supports the previously identified role for nutritional status in homocysteine metabolism, 18,72 and is consistent with the beneficial effects of folate fortification. 73 We further observed that the mean plasma folate concentration for this study population was very low (3.8 and 3.4 ng/ml for men and women, respectively). A level of 3 ng/ml has often been used as a cutoff for inadequate folate status.…”

Homocysteine and cognitive function in elderly people

“…This has resulted in Homocysteine and dementia increased levels of serum folic acid and of RBC folate in the entire population. 56 The effects of these increases on homocysteine levels in the elderly population are largely unknown, but interesting data have started to emerge. A Chilean study recently reported that folic acid fortification of flour had a moderate lowering effect on homocysteine levels in the elderly population (mean age 74.3 years).…”