Normal-weight women who drank alcohol in moderation were less likely than women who didn't drink at all to become overweight or obese over more than a dozen years of follow-up.

Those who drank the equivalent of one to two drinks a day -- be it beer, wine, or liquor -- were 30% less likely than non-drinkers to become overweight or obese.

More info:

http://www.webmd.com/diet/news/20100308/moderate-drinking-linked-to-weight-control