Last reviewed and revised February 27, 2013
In medical school, I was taught to routinely ask each patient about his or her alcohol intake. I often heard this answer: "I'll have a glass of wine with dinner, but I never touch the hard stuff." Sometimes, the answer was more concerning: "I like to down a couple of six-packs watching the ball game, but it's just beer." The assumption that many people make is that beer or wine is safer than hard liquor, such as vodka or whiskey.
For most of the ways alcohol can affect your health, that assumption is wrong.
Current evidence suggests that all types of alcoholic drinks can cause similar trouble, taking into account how they are typically served (more concentrated forms of alcohol are served in smaller portions) and how fast they are ingested. In terms of the most important dangers of alcohol — an increased risk of liver damage, esophageal and liver cancer, breast cancer, osteoporosis, risky sexual behavior, trauma or accidents — there is little difference between one bottle (12 ounces) of beer, one glass (five ounces) of wine and one mixed drink (typically containing one to two ounces of hard liquor).
The other ingredients, such as hops, grains, antioxidants or those wild colors in tropical mixed drinks, aren't thought to have much effect on the toxic effects of alcohol, although they may affect taste, caloric content and how fast or how many drinks are ingested. Perhaps it's the higher concentration of alcohol in mixed drinks, the stronger taste or simply the name hard liquor that promotes the impression that such drinks are more dangerous.
There is at least one exception to this rule: Drinking beer seems to increase the risk of gout more than other types of alcohol.
The Effects of Alcohol on Your Body
The effects of alcohol may depend most on your gender, body makeup and heredity:
As it does with any food or drink, the stomach absorbs alcohol into the bloodstream within minutes. The blood supply from the intestinal tract is routed directly to the liver so that what we eat or drink can be "detoxified" and nutrients delivered to where they are needed: iron to the blood-forming bone marrow, sugar to working muscles and so on.
The problem is that alcohol in any form is a direct toxin to liver cells. In low amounts, no significant harm is done — in fact, the liver is among the most forgiving organs in the body, with a tremendous capacity to regenerate or recover from injury. And the multitude of tasks the liver normally performs is staggering. Besides the detoxifying effects on ingested substances, it also produces essential proteins, including those that control blood clotting; it makes bile salts that aid in absorption of fats; and it produces hormones that help balance blood sugar.
But with large exposure to alcohol over a long period, liver injury leads to the formation of scar tissue. Cirrhosis is the worst form of scarring, in which the liver becomes shrunken and unable to perform its normal functions. When the liver fails, death may soon follow unless a liver transplant is performed.
Are There Any Benefits?
Several studies suggest a reduction in heart attacks among moderate drinkers (usually defined as those who drink three to nine alcoholic drinks each week), although it's not clear whether it's the alcohol itself, other lifestyle behaviors or the nonalcoholic ingredients that have this effect. Other benefits have been reported, including a decreased risk of diabetes and gallstones.
Does the type of alcohol matter with respect to health benefits? There's some evidence that red wine, with antioxidants not found in other sources of alcohol, may have more specific beneficial effects on cardiovascular risk and the tendency of the blood to form clots. However, such evidence isn't compelling; whether the type of alcoholic beverage matters for any beneficial effects isn't known.
The Bottom Line
When you saddle up to the bar and choose your next drink, keep this in mind: Whether you drink beer, wine or cognac, alcohol is alcohol. Whatever your choice of alcoholic beverage, moderation is essential — your liver can't tell the difference.
Robert H. Shmerling, M.D. is associate physician at Beth Israel Deaconess Medical Center and associate professor at Harvard Medical School. He has been a practicing rheumatologist for over 20 years at Beth Israel Deaconess Medical Center. He is an active teacher in the Internal Medicine Residency Program, serving as the Robinson Firm Chief. He is also a teacher in the Rheumatology Fellowship Program.