Blood Folate And Vitamin B12: United States, 1988-1994
Series 11, No. 243.
Blood Folate and Vitamin B12: United States, 1988-94. 84 pp. (PHS) 99-1693. GPO stock
number and price forthcoming
This report presents national estimates of serum and red blood cell (RBC) folate and serum vitamin B12 distribution for persons 4 years and older, by sociodemographic variables. Results of an investigation to determine correlates of blood concentrations of these vitamins are also reported.
The average serum folate concentration for all persons in the U.S. 4 years and older, excluding pregnant females, is 7.2 ng/mL. Non-Hispanic whites had higher mean serum folate than non-Hispanic blacks (p<.01), 7.5 ng/mL compared with 5.8 ng/mL for non-Hispanic whites and non-Hispanic blacks respectively. The average serum folate for all males was lower than for all females (p<.01), 6.8 ng/mL compared with 7.5 ng/mL for males and females respectively.
The mean BC folate concentration for all persons in the U.S. 4 years and older, excluding pregnant females, is 196 ng/mL. RBC folate concentrations have patterns similar to serum folate. That is, non-Hispanic whites have higher mean RBC folate than Mexican Americans and non-Hispanic blacks, with an age-adjusted mean of 204 ng/mL for non-Hispanic whites, while the mean concentration for Mexican Americans is 180 ng/mL (p<.01), and 150 ng/mL (p<.01) for non-Hispanic blacks.
The mean serum B12 concentration for all persons in the U.S. 4 years and older, excluding pregnant females, is 518 pg/mL. Whereas the distribution of serum and RBC folate are slightly skewed (skewness=6.18 for serum folate and skewness=2.55 for RBC folate), the distribution of serum vitamin B12 concentrations is highly skewed (skewness =42.19). Non-Hispanic whites have the lowest concentrations with a median of 446 pg/mL (95% limits: 436-456 pg/mL), while Mexican-Americans have a median of 499 pg/mL (95% limits: 473-530 pg/mL) and non-Hispanic blacks have the highest median concentration, 568 pg/mL (95% limits: 553-582 pg/mL).
Keywords: folate, vitamin B12, NHANES III, nutritional status, biochemistries, red blood cell, serum
This page last reviewed
January 11, 2007