If you are like many Americans, you drink alcohol at least occasionally. For many people, moderate drinking is probably safe. But drinking too much can be harmful, so it's important to know how alcohol affects you and how much is too much.

How does alcohol affect the body?

Alcohol is a central nervous system depressant. This means that it is a drug that slows down brain activity. It can change your mood, behavior, and self-control. It can cause problems with memory and thinking clearly. Alcohol can also affect your coordination and physical control.

Alcohol also has effects on the other organs in your body. For example, it can raise your blood pressure and heart rate. If you drink too much at once, it could make you throw up.

Why are the effects of alcohol different from person to person?

Alcohol's effects vary from person to person, depending on a variety of factors, including:

• How much you drank
• How quickly you drank it
• The amount of food you ate before drinking
• Your age
• Your sex
• Your race or ethnicity
• Your physical condition
• Whether or not you have a family history of alcohol problems

What is moderate drinking?

• For most women, moderate drinking is no more than one standard drink a day
• For most men, moderate drinking is no more than two standard drinks a day

What is a standard drink?

In the United States, a standard drink is one that contains about 14 grams of pure alcohol, which is found in:

• 12 ounces of beer (5% alcohol content)
• 5 ounces of wine (12% alcohol content)
• 1.5 ounces or a "shot" of distilled spirits or liquor (40% alcohol content)

Who should not drink alcohol?

Some people should not drink alcohol at all, including those who

• Are recovering from an alcohol use disorder (AUD) or are unable to control the amount they drink
• Are under age 21
• Are pregnant or trying to become pregnant
• Are taking medicines that can interact with alcohol
• Have medical conditions that get can worse if you drink alcohol
• Are planning on driving
• Will be operating machinery

If you have questions about whether it is safe for you to drink, talk with your health care provider.

What is excessive drinking?

Excessive drinking includes binge drinking and heavy drinking:

• Binge drinking is drinking so much at once that your blood alcohol concentration (BAC) level is 0.08% or more. For a man, this usually happens after having 5 or more drinks within a few hours. For a woman, it is after about 4 or more drinks within a few hours.
• Heavy drinking is having 15 or more drinks a week for a man. For a woman, it is having 8 or more drinks a week.

Binge drinking raises your risk of injuries, car crashes, and alcohol poisoning. It also puts you of becoming violent or being the victim of violence.

Heavy drinking over a long period of time may cause health problems such as

• Alcohol use disorder
• Liver diseases, including cirrhosis and fatty liver disease
• Heart diseases
• Increased risk for certain cancers
• Increased risk of injuries

Heavy drinking can also cause problems at home, at work, and with friends. But treatment can help.

NIH: National Institute on Alcohol use disorder and Alcoholism.