After alcohol is absorbed into the bloodstream it leaves the body in two different ways. About ten percent leaves through exhalation (breathing), perspiration and urination, and the remaining alcohol is metabolized by the body.

The human body metabolizes alcohol at the rate of .015 of blood alcohol concentration (BAC) every hour regardless of height, weight, sex, or race. (It is the blood alcohol levels that may be affected by these characteristics, not the metabolism of alcohol, as people sometimes believe.)

Thus after a night of relatively light drinking, a person with a BAC of .15 will have no measurable alcohol in the bloodstream after ten hours (.15 divided by .015 = 10).A person with a BAC of .10 will have no alcohol in the system after about six and half hours; a BAC of .08 will be completely diminished in about five and half hours; .05 a little over three hours; and .02 in a little over an hour.  Be careful though. It’s possible to drink so much that you’ll still be legally drunk the next daymaybe even on the way to work.

Though a person cannot control the rate at which his BAC decreases, he can control the rate at which his BAC increases. Here are some helpful tips to avoid getting drunk too quickly and in maintaining a moderate BAC:

  • Don’t be fooled by different types of alcohol. Standard serving sizes of beer, wine, or liquor (mixed or straight) each contain virtually identical amounts of pure alcohol, which is about .6 ounces. You will not get less drunk drinking beer versus wine. Your blood alcohol levels will be the same.
  • Eat food while you drink. Food, especially high protein food such as meat, cheese, and eggs will help slow the absorption of alcohol into your body. Eating carbohydrates and other types of food do not have nearly the same effect though they may cause you to drink more slowly or feel full and drink less.
  • Drink slowly. Sip your drink, don’t chug, and alternate alcoholic drinks with non-alcoholic drinks or space your alcoholic drinks out over a period of time. A good general guideline is one drink per hour.
  • Keep active. When people are active they tend to drink less and they may lose more alcohol through perspiration. Studies have shown that vigorous exercise, like the type you may get from hours of dancing, decreases BAC levels.
  • Watch out for fruity drinks. They tend to have more alcohol in them than other types of mixed drinks, and the alcohol taste is usually masked with sweetness, making it easy to drink a lot for a long time or in a short period of time.

The metabolic processing of alcohol cannot be speeded up. Drinking coffee, exercising or taking showers have no effect on alcohol metabolism or blood alcohol levels. Only time heals the effects of heavy drinking.

If you do plan on drinking, also plan on not driving. Have a friend be a designated driver who doesn’t drink alcohol that evening, or call a cab.  If you drink a lot, you won’t be able to wait it out until you get sober, unless you don’t mind sleeping in your car all night.

If you’re unsure about how much you’ve had or whether you should be driving, be sure to test yourself for BAC if a breath alcohol tester is available.