Background: There is uncertainty as to whether regular alcohol consumption contributes directly to weight gain and the risk of obesity.
Objective: We examined the relation between alcohol intake and body weight and the association between changes in alcohol intake and in body weight over 5 y of follow-up.
Design: This was a prospective study of 7608 men aged 40-59 y drawn from general practices in 24 British towns, excluding persons with known diabetes. Five years after screening, 6832 men then aged 45-64 y and without diabetes completed a postal questionnaire on changes in alcohol intake and body weight.
Results: Mean body mass index (BMI; in kg/m(2)) and the prevalence of men with a high BMI (>or= 28; top quintile of the BMI distribution) increased significantly from the light-moderate to the very heavy alcohol intake group even after adjustment for potential confounders. Similar patterns were seen for all types and combinations of alcohol. After 5 y of follow-up, stable and new heavy drinkers (including very heavy drinkers of >or= 30 g/d) showed the greatest weight gain and had the highest prevalence rates of high BMI. Weight change patterns in heavy drinkers at baseline who reduced their intake were not significantly different from those in the stable none-occasional group but showed more weight loss and less weight gain than in the stable or new heavy drinkers.
Conclusion: Heavy alcohol intake (>or= 30 g/d) contributes directly to weight gain and obesity, irrespective of the type of alcohol consumed.