Lower folate status is a risk factor for cardiovascular disease and certain cancers. Since pre-menopausal African American women have high rates of obesity, breast and colorectal cancers, understanding the link between obesity and folate metabolic status offers a mechanistic insight into the obesity-cancer connection.
We assessed the associations between serum total folate, 5-methyltetrahydrofolic acid (5MeTHF), pteroylmonoglutamic acid (PGA), 5-formyltetrahydrofolic acid (5FoTHF), tetrahydrofolic acid (THF]), plasma vitamin B12, and total homocysteine concentrations and obesity in pre-menopausal AA women (n=113).
This was a cross sectional study conducted at the baseline segment of a dietary intervention study in which fasting samples were used for folate, vitamin B12, and homocysteine measurements.
In multivariable analysis, serum total folate concentrations were 14.5% lower in the overweight (BMI 25-29.9) and obese (BMI 30-39.9) women, and 25% lower in the extremely obese (BMI >40) compared to normal weight (BMI <24.9) women (p-trend=0.08). For 5MeTHF, the major form of folate in circulation, overweight women had 15.2% lower, obese women 15.7% lower, and extreme obese women 26.9% lower concentrations than normal weight women (p-trend=0.06). Also, the overweight and obese women were more likely to be in the lower 50th percentile of serum total folate (p-trend=0.03) and 5MeTHF (p-trend=0.08) concentrations compared to the normal weight women. There were no significant associations between BMI and the minor folate species, plasma B12, and homocysteine.
With obesity at epidemic levels, these data, if confirmed by prospective or randomized controlled studies, have important public health implications.
Citation Information: Cancer Prev Res 2008;1(7 Suppl):A97.
Seventh AACR International Conference on Frontiers in Cancer Prevention Research-- Nov 16-19, 2008; Washington, DC