Drinking alcohol affects the body in many ways. These effects can lead to physical and mental changes that can put alcohol users and others at risk of injury or death. Possible dangers include falls, household accidents, and car crashes.

When a person drinks beer, wine, or another alcoholic drink, the alcohol quickly enters the bloodstream and is then carried throughout the body. The alcohol gets broken down through metabolism, the process of converting substances we consume to other compounds that the body either uses or removes. Alcohol is distributed throughout the body, affecting the brain and other tissues, until it is completely metabolized. 

A drink of alcohol stays in the body for about 2 hours after being consumed. This period of time can vary depending on the person’s weight, gender, and other factors. When a person drinks, the concentration of alcohol in the blood builds to a peak, and then decreases as metabolism breaks the alcohol down. At first, alcohol often makes people feel relaxed and happy. Later, it can cause drowsiness or confusion. 

The small intestine and the stomach absorb most of the alcohol after drinking. A small amount leaves the body through breath and urine. Eating slows the absorption of alcohol. If people drink more alcohol than their bodies can absorb, they become drunk. 

Drinking too much alcohol affects many parts of the body. It can be especially harmful to the liver, the organ that metabolizes (breaks down) alcohol and other harmful substances. People who drink heavily for a long time can develop diseases such as liver inflammation (alcoholic hepatitis) or severe liver scarring (cirrhosis). Alcohol-related liver disease can cause death.

Alcohol not broken down by the liver goes to the rest of the body, including the brain. Alcohol can affect parts of the brain that control movement, speech, judgment, and memory. These effects lead to the familiar signs of drunkenness: difficulty walking, slurred speech, memory lapses, and impulsive behavior. Long-term heavy drinking can shrink the frontal lobes of the brain, which impairs thinking skills.

Drinking alcohol can affect the heart in good and bad ways. On the one hand, studies have shown that moderate drinking—defined for adults over 65 as no more than one drink a day for men and women—can lower the chances of developing heart disease. On the other hand, heavy drinking— either all at once or over time—can damage the heart. Long-term alcohol use can also result in high blood pressure, which increases a person’s risk of heart disease. However, blood pressure can go back to normal within a few months after drinking stops if there is not much damage to the heart. 

 Alcohol affects men and women differently. In general, older men are more likely to drink alcohol compared with older women. According to a British government study, men account for about 66 percent of people who drink weekly, while women account for only about 44 percent. But women of all ages are affected more easily than men by the alcohol consumed. Also, women have less water in their bodies than men, so alcohol is more concentrated in the smaller water volume. As a result, women may become more impaired than men after drinking the same amount.

Drinking for a long time is more likely to damage a woman’s health than a man’s health. Research suggests that as little as one drink per day can slightly raise the risk of breast cancers in some women, especially those who have been through menopause or have a family history of cancer. But it is not possible to predict how alcohol will affect the risk for cancer in any one woman. 

In addition, although light to moderate drinking has not been shown to increase the risk for developing liver cancer, exceeding these levels increases the risk for both men and women. On average, studies have demonstrated an increased risk of 19 percent per 10 grams of alcohol per day for women, compared to only 3 percent for men. If consumed at all, limit alcohol to a maximum of 2 drinks a day for men and 1 drink a day for women, below the age of 65.