Does obesity modify the association of supplemental folic acid with folate status among nonpregnant women of childbearing age in the United States
Birth Defects Research Part A: Clinical and Molecular Teratology, 05/30/2012
Tinker SC et al. – These results do not support a straightforward modification of the relationship between supplemental folic acid intake and folate status by BMI. In this population, BMI may affect the body distribution of folate, as reflected by lower serum and higher RBC folate levels in obese women who do not use supplements.Methods
- Authors analyzed data from the National Health and Nutrition Examination Survey, representative of the noninstitutionalized civilian U.S. population, to assess whether body mass index (BMI; normal weight, overweight, and obese categories) modified the association between supplemental folic acid intake and folate status.
- They estimated the geometric mean concentration among nonpregnant women of childbearing age (15–44 years) during the postfortification period of: serum folate (2003–2008); red blood cell (RBC) folate (2007–2008); and plasma total homocysteine (tHcy; 2003–2006), adjusted for age, race and ethnicity, and total dietary folate expressed as dietary folate equivalents for strata of supplement use and BMI.
- BMI was inversely associated with serum folate among women who did not use supplements containing folic acid; no differences between women in different BMI categories were observed among supplement users.
- Regardless of supplement use, obese women had the highest RBC folate concentrations.
- There were no differences in tHcy by BMI, regardless of supplement use.