Smoking and passive smoking as conditioners of folate status in young women.
OBJECTIVE: For women of fertile age, an adequate supply of folate is important for preventing a range of health problems, especially congenital malformations in their offspring. Since congenital deformities are more common in children of mothers who smoke, the objective was to analyse the folate status of smokers, passive smokers and non-smokers. METHODS: Folate intake was monitored in 319 women aged 18-35 (112 smokers, 100 passive smokers and 107 non-smokers) using a three day food record. Serum and erythrocyte folate concentrations were measured by radioimmunoassay. Exposure to tobacco smoke was established by a questionnaire on present and past tobacco consumption, the number of hours in contact with smokers, and by assessing urine cotinine concentrations. RESULTS: The folate intake of smokers (S) (159.1 +/- 65.7 microg/day) and passive smokers (PS) (165.2 +/- 66.6 microg/day) was lower than that of non-smokers (N) (181.7 +/- 72.4 microg/day) (p < 0.05 between S and N). No subject fully met the recommended intake of the vitamin, but S and PS subjects both took less than N subjects (39.8 +/- 16.4% and 41.3 +/- 16.6% compared to 45.4 +/- 18.1% respectively). Serum folate concentrations were also lower in S and PS subjects grouped together (16.6 +/- 5.9 nmol/L) compared to N subjects (18.4 +/- 6.7 nmol/L) (p < 0.05). CONCLUSIONS: None of the studied women took the 400 microg/day of folate recommended. 6.7% had serum folate concentrations of < 9.2 nmol/L. The situation was worse in S and PS subjects, which might contribute to an increased risk of developing certain diseases and to giving birth to children with congenital deformations.