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Many Americans drink alcohol at least occasionally. The Dietary Guidelines for Americans say that adults of legal drinking age should either not drink or drink in moderation. Drinking less is better for your health than drinking more. Also, there are some people who should not drink at all.

If you are going to drink, 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 drink
  • How often you drink
  • Your age
  • Your sex
  • Your genetics
  • Your overall health
  • Whether or not you have a family history of alcohol problems
What is moderate drinking?
  • For most women, moderate drinking is no more than 1 standard drink a day
  • For most men, moderate drinking is no more than 2 standard drinks a day

Even though moderate drinking may be safe for many people, there are still risks. Moderate drinking can raise the risk of death from certain cancers and heart diseases.

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 regular 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 in recovery from an alcohol use disorder (AUD)
  • Are 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 or doing activities that require skill, coordination, and alertness

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 alcohol use:

  • Binge drinking is drinking so much at once that your blood alcohol concentration (BAC) level is 0.08% or more:
    • For men, this usually happens after having 5 or more drinks within a few hours.
    • For women, it is usually after about 4 or more drinks within a few hours.
  • Heavy alcohol use means:
    • For men, having more than 5 drinks on any day or more than 15 drinks per week.
    • For women, having more than 4 drinks on any day or more than 8 drinks per week.

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

Heavy alcohol use over a long period of time may cause health problems such as:

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

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

NIH: National Institute on Alcohol Abuse and Alcoholism