Effects of moderate red wine consumption on liver fat and blood lipids: a prospective randomized study

Background: There have been no human prospective randomized studies of the amount of alcohol that can induce hepatic steatosis.

Methods: Thirty-two healthy women and twelve healthy men (34 +/- 9 years of age) were randomized to consume 150 ml of red wine/day for women (16 g ethanol/day) or double that amount for men (33 g ethanol/day), or to alcohol abstention for 90 days. Participants underwent proton-nuclear magnetic-resonance spectroscopy for measurement of hepatic triglyceride content (HTGC). Blood samples for assessment of cardiovascular risk were drawn before and after the intervention.

Results: After exclusion of three subjects with steatosis at baseline a trend towards increased HTGC was apparent for red wine (before median: 1.1%, range 0.2-3.9%, after median: 1.1%, range 0.5-5.2 %, P = 0.059) a difference that was statistically significant compared with abstainers (p = 0.02). However, no subject developed hepatic steatosis. Low-density lipoprotein (LDL)-cholesterol was lowered by red wine (-0.3 mmol/l, SE -0.1, 95% CI -0.6 to -0.04).

Conclusions: Moderate consumption of red wine during three months increased HTGC in subjects without steatosis at baseline. However, since not a single participant developed steatosis we suggest that the threshold of alcohol consumption to define nonalcoholic fatty liver disease should not be lower than the amount in our study.