Look around any bar and chances are you'll spot some epic beer bellies. But you'll probably also see trim, toned guys knocking back drinks sans weight-gain regrets.
What gives? Well, it's a quandary that has left researchers volleying studies back and forth since before anyone ever heard of a healthy happy-hour habit. The good news (at least for guys wanting to shed a few) is that we have control over alcohol's role in our weight. It's all about how often—and how hard—we hit the bar.
According to a 2011 study published in The Archives of Internal Medicine, moderate drinkers tend to be thinner than teetotalers. Why? Ethanol—whether it's in wine, on the rocks, or in a pilsner glass—improves your body's response to the hormone insulin, which regulates blood sugar. Keep your blood sugar in check and you can prevent your body from shuttling glucose straight into your fat cells. One Harvard School of Public Health study even found that having one to two alcoholic drinks a day can reduce your risk of diabetes by 36 percent.
Plus, by increasing your heart rate, alcohol actually fires up your fat burners for about an hour after you take your last sip, according to Eric Rimm, an associate professor of epidemiology and nutrition at Harvard Medical School and chairman of the 2010 review of alcohol in the federal dietary guidelines. One recent study from Japan even suggests that if you're a microbrew man, your post-drink metabolic boost might last a little longer. Why? The naturally occurring flavonoids in beer's hops can increase muscle mass. And as you know, more muscles equal a faster metabolism—not to mention a chiseled bod.
Now, the caveat: The bennies only go for those who drink moderately, which is probably a lot less than you think. Case in point: The slim drinkers in the Archives study were served no more than two four-ounce glasses of wine or two 1.5-ounce shots of liquor a day. According to the National Institutes of Health, most bartenders serve glasses containing up to three times the alcohol they should, making it difficult for you to find the "two drink" sweet spot that most researchers opine is healthy for men.
We know what you're thinking and, no, saving all of your drinks for the weekend won't work for your weight. Since your body adjusts to the amount you drink, but needs time to do so, it simply can't keep up with straightlaced weekdays and off-the-wagon weekends. As a result, when you drink, your body stores whatever calories are in your gut at the time as fat—whether they're from the mixers in your glass or the peanuts on the bar.
And, according to a recent study published in the American Journal of Clinical Nutrition, a lot of calories are probably sitting in your stomach with that alcohol. Researchers analyzed data from a National Health and Nutrition Examination Survey and found that men consume an extra 433 calories (about the equivalent of a McDonald's double cheeseburger!) on days they have just a couple of drinks. While 61 percent of the caloric increase comes from the alcohol itself—it packs seven calories per gram—men also ate more saturated fat on days they drank, according to the study.
While booze-induced bad judgment undoubtedly has something to do with the results, alcohol can also trick your brain into thinking you need to eat, according to one Swedish study. Researchers found that downing just three drinks can cut the body's levels of the feel-full hormone leptin by 30 percent. That's more than enough to make a midnight pizza run feel essential to survival.
The bottom line: Alcohol can help trim the fat from your frame—just remember to keep it slow and steady. Otherwise, the bar's resident booze belly will be yours.