Slide 1 of 15
An apple a day keeps the doctor away, but what about a beer a day? Or for that matter, a glass of wine or even a shot of hard liquor?
It's well-established that drinking too much, even every once in a while, is bad for you, but there's often uncertainty regarding how moderate drinking affects health. There are some negatives, and some positives, so decisions about whether to drink really depend on people's individual situations, said Dr. Sam Zakhari, the director of the metabolism and health effects at the National Institute of Alcohol Abuse and Alcoholism.
But first, establishing what "moderate drinking" means is key for anyone looking for health benefits associated with alcohol, Zakhari said. For men, moderation means no more than two drinks a day, while for women, moderation means no more than one drink a day. Zakhari emphasized that drinking seven drinks in one day, and not drinking the rest of the week, will have dramatically worse effects on health, even though it averages to the same levels of consumption.
According to Dr. Robert Gish, of the University of California, San Diego School of Medicine, moderate levels can be a bit higher daily, at one and a half drinks for women and two to three drinks daily for men. But it's important to take a couple days off each week from drinking at all, Gish said.
Even though drinking at moderate levels has some benefits, as soon as people start drinking more than the recommended amounts, benefits diminish quickly, and problems arise, Gish said.
"If you tell people they can have a drink, or a drink and a half a day, they tend to overconsume," Gish said.
Zakhari noted that one drink is equal to one bottle of beer, one glass of wine or one shot of liquor. Drinking a large glass of wine counts as two drinks, not one. But, he added, because the benefit is from the alcohol itself, positive results can come from habitual, moderate consumption of any of these types of alcohol.
"A drink is a drink is a drink," he said.
Here are some of the health effects of moderate drinking — there are some benefits, but also some harms.
Decreases risk of heart disease and heart attackSlide 2 of 15
Decreases risk of heart disease and heart attack
When consumed in low doses, alcohol can reduce blood pressure, though when consumed in excess, in can have the opposite effect.
Additionally, alcohol helps to clear fat from the arteries, and reduces the blood's tendency to clot, Zakhari said. These effects help to limit the chances of heart disease and heart attack. Inflamed arteries that block blood flow are problematic for the heart, as it doesn't receive the oxygen it needs. Alcohol consumption encourages smoother blood flow, thus lowering the risk of heart disease.
Red wine also has the added effect of lowering cholesterol levels, although that benefit is specific to that beverage, Gish noted.Slide 3 of 15
Reduces risk of strokeSlide 4 of 15
Reduces risk of stroke
For the same reasons that moderate drinking can lower the risk of heart attack, it also reduces risk of certain types of stroke.
The most common type or stroke, called ischemic stroke, occurs when a vessel bringing blood to the brain gets "clogged," Zakhari said. "The alcohol helps the blood go to the brain, and therefore it reduces stroke."
The other type of stroke, hemorrhagic, occurs when blood seeps out of a brain blood vessel. Because alcohol thins blood, it actually makes this type of stroke worse, but because hemorrhagic strokes only account for 20 percent of all strokes, there is still a net benefit, Zakhari said.
The benefits of alcohol on heart disease and stroke allow some people to argue that moderate consumption is associated with longer lifespan.Slide 5 of 15
How well you sleep at nightSlide 6 of 15
How well you sleep at night
A glass of wine may be a pre-bedtime routine for some, but it's important to understand how the alcohol affects your sleep. For most people, one serving of alcohol before bed will have no effect on sleeping. But more than one drink might — alcohol helps people fall asleep, but makes it more likely they'll wake up during the night.
"You will sleep faster, but not better," because alcohol interferes with REM sleep, Zakhari said.
Additionally, people often use an alcoholic drink as a means to fall asleep, particularly if they've drank lots of caffeine during the day, Gish said. This combination may seem to work on the surface, but it is not a healthy in the long run, Gish said. He tells patients with sleep problems to cut all alcohol and caffeine out for two weeks to understand where the problems lay.Slide 7 of 15
Slight diuretic effectSlide 8 of 15