Effect of folic acid fortification of foods on folate intake in female smokers with cervical dysplasia.

OBJECTIVE: We investigated the effect of folic acid fortification of enriched cereal grains on folate intake in women of predominantly childbearing age at high risk for cervical cancer.

METHODS: Subjects in this cross-sectional study were 77 women randomized between November 1999 and December 2000 in the Women's Intervention to Stay Healthy (WISH), a clinical trial evaluating the effect of a tobacco control intervention on the progression of cervical dysplasia. All subjects were cigarette smokers, had a previously abnormal Papanicolaou test, and were positive for high-risk human papillomavirus at entry. Dietary intake was assessed with food-frequency questionnaires completed at the baseline visit for WISH. The effect of folic acid fortification on folate intake was assessed by using pre- and postfortification folate databases to estimate folate intake.

RESULTS: Mean folate intake assessed with the postfortification database was 63% higher than intake assessed with the prefortification database: 417 versus 256 microg/d of dietary folate equivalents (P < 0.0001). The proportion of subjects below the estimated average requirement for folate was smaller after fortification than before fortification: 40.3% versus 75.3% (P < 0.0001). Several foods, including white bread, cheese dishes, spaghetti, and rice, became major sources of folate as a result of fortification.

CONCLUSIONS: Folic acid fortification resulted in an increased intake of folate in these subjects. However, even with fortification, folate intake in a large proportion of these women remained below recommended levels. These results should be considered before decisions regarding future levels of folic acid fortification are made.