Long-term intake of trans-fatty acids and risk of gallstone disease in men.

BACKGROUND: The consumption of trans-fatty acids adversely affects blood lipid levels. The relationship with the incidence of gallstone disease is unknown.

METHODS: We prospectively studied consumption of trans-fatty acids in relation to the risk of gallstone disease in a cohort of 45,912 men. trans-Fatty acid consumption was assessed using a validated semiquantitative food frequency questionnaire. Newly diagnosed gallstone disease, by radiology or cholecystectomy, was ascertained biennially.

RESULTS: During 14 years of follow-up, we documented 2356 new cases of symptomatic gallstones. After adjusting for age and other potential risk factors, we found that compared with men in the lowest quintile of dietary intake of trans-fatty acids, the relative risk (RR) of gallstone disease for those in the highest quintile was 1.23 (95% confidence interval [CI], 1.04-1.44; P for trend, .03). Among individual trans-fatty acids, the RR for trans-oleic fatty acid, when extreme quintiles were compared, was 1.24 (95% CI, 1.06-1.45; P for trend, .02). Intakes of trans-palmitoleic fatty acid (RR, 1.09; 95% CI, 0.90-1.31), trans,trans 18:2 fatty acid (RR, 1.14; 95% CI, 0.96-1.34), and cis-trans 18:2 fatty acid (RR, 1.00; 95% CI, 0.86-1.16) were not significantly associated with the risk.

CONCLUSIONS: Our results suggest that a higher intake of trans-fatty acids modestly increases risk of gallstone disease. This adds to the concern that partial hydrogenation of vegetable oils to form shortening and margarine can lead to adverse health effects.