Heavy drinking does not have any health benefits. Apart from a wide range of negative health consequences, including an increased risk for many types of cancer, it also contributes to injury, violence, increased body weight, and impaired cognitive function. It's responsible for about 79,000 deaths a year in the U.S.

The U.S. government's Dietary Guidelines for Americans defines moderate drinking as no more than one drink per day for women and no more than two drinks per day for men. Women are considered heavy drinkers if they drink more than three drinks on any day or more than seven drinks per week. Men are heavy drinkers if they drink more than four drinks on any day or more than 14 per week.

A drink is defined as 0.6 ounces of alcohol -- roughly the amount in 12 ounces of beer, 5 ounces of wine, or 1.5 ounces of 80-proof liquor.

Excessive drinking can have a wide range of negative effects on your health, including an increased risk of diabetes, cirrhosis of the liver, high blood pressure, and stroke. Excessive drinking also can increase your risk for a variety of cancers, including mouth, larynx, and esophageal cancers, breast cancer, and cancers of the liver, gastrointestinal tract, and colon.

Long-term heavy drinking actually changes your brain. It may shrink both the overall mass of the brain and the size of the brain's cells. These and other negative effects can reduce your mental abilities, with deficits in learning, memory, and problem-solving. Heavy long-term drinking also can harm your mood, sleep, and motor skills. Abstinence -- avoiding alcohol -- can partially reverse these effects.

There is strong evidence that moderate alcohol consumption is associated with a lower risk of heart disease, according to the U.S. government's Dietary Guidelines for Americans. One reason might be that moderate drinking raises levels of "good" cholesterol (HDL).

However, the key word here is "moderate."  Long-term heavy drinking weakens the heart muscle and can contribute to high blood pressure, stroke, heart failure, and other cardiovascular problems.

Moderate alcohol consumption is associated with a reduced risk of death from all causes in middle-aged and older adults. It's not clear why, but some researchers think it's likely due to the protective effects of moderate drinking against heart disease, stroke, and diabetes.

The American Heart Association urges people who don't drink not to start. The U.S. government's Dietary Guidelines for Americans agrees, stating that people should not take up drinking because of potential health benefits. The guidelines point out that moderate drinking also is associated with increased risk of breast cancer, violence, drowning, falls, and car crashes.

Strong evidence suggests that moderate consumption of red wine is good for the heart. According to the American Heart Association, red wine increases good cholesterol, and the grape skin provides flavonoids and other antioxidant substances that protect the heart and vessels. Red wine also may have a protective effect against prostate cancer and certain other cancers, probably because of antioxidants and a substance called resveratrol. Red wine does not appear to protect against breast cancer.

Alcoholic beverages can be a significant source of extra calories. If you drink a lot of any alcoholic beverage, you can pack on the pounds quickly. For moderate drinkers, the choice of beverage can make a big difference. Most of us know that beer -- with about 149 calories per drink -- is high in calories, but the caloric content of many cocktails (1 pina colada = 460 calories) may be surprising. Compared to many mixed drinks, wine (about 90-95 calories per glass) is much lower in calories, as is light beer (about 110 calories).

Although researchers caution that more study is needed, evidence suggests that light to moderate drinking in early adult life may help protect against dementia in later life. Older people who drink in moderation also may reduce their risk of dementia and cognitive decline.

As with other potential benefits, these positive effects are associated only with light or moderate -- but not heavy -- drinking.

Three-quarters of all alcohol consumed in the U.S. is consumed during binge drinking (four or more drinks on one occasion for women and five or more for men), according to the CDC. For people under 21, binge drinking accounts for 90% of all alcohol consumption.

Binge drinking is associated with a wide variety of health issues, including an increased risk for high blood pressure, heart attack, sexually transmitted diseases, and unintended pregnancy. It's also a risk factor for injury, violence, and suicide.

Binge drinking is more common among educated, higher-income people. People with lower levels of education and income are less likely to binge drink. The correlation of higher incomes with binge drinking is a likely explanation for why cell phone users are more likely to binge drink than people who only have a land line.

Researchers speculate these differences might be the result of cultural factors, differences in local laws, or a general lack of public prevention efforts.

Most binge drinkers are casual drinkers who sometimes drink to excess. This is a type of alcohol abuse -- defined by the CDC as "a pattern of drinking that results in harm to one’s health, interpersonal relationships, or ability to work."

Alcohol abuse can lead to alcohol dependency, also known as alcohol addiction or alcoholism. According to the CDC, alcoholism is a disease marked by a strong craving for alcohol, an inability to limit drinking, and continued drinking "despite repeated physical, psychological, or interpersonal problems."

Drinking caffeine and alcohol together may lead to hazardous behavior because caffeine can mask clues about a person's level of intoxication. Drinkers who mix alcohol and caffeine also are twice as likely to report being taken advantage of sexually or to ride with a driver who was under the influence of alcohol, according to a 2008 study.

Women are more vulnerable to alcohol for a variety of reasons. First, women tend to weigh less than men, so a drink delivers proportionately more alcohol. But even in the case of men and women who weigh the same, alcohol hits women harder because they metabolize it differently. Alcohol is diluted by the body’s water content, and women tend to have a lower water content. This means that alcohol is not as diluted in their bodies, and their organs are exposed to more alcohol.

Women are at higher risk for negative health consequences of drinking, including liver, brain, and heart damage.

Studies suggest that men who drink a glass of red wine a day may cut their risk of prostate cancer in half. According to the National Cancer Institute, this may work best for the most aggressive forms of prostate cancer.

However, the group warns, heavy drinking may increase the risk of other cancers.