When a person drinks an alcoholic beverage, about 20 percent of the alcohol is absorbed in the stomach and about 80 percent is absorbed in the small intestine. How fast the alcohol is absorbed depends upon several things:
- The biological sex of the drinker. Alcohol is metabolized differently in women and men, due to factors like body composition.
- The concentration of alcohol in the beverage. The greater the concentration, the faster the absorption.
- The type of drink. Carbonated beverages tend to speed up the absorption of alcohol.
- Whether the stomach is full or empty. Food in the belly slows down alcohol absorption.
After absorption, the alcohol enters the bloodstream and dissolves in the water of the blood. The blood carries the alcohol throughout the body. The alcohol from the blood then enters and dissolves in the water inside each tissue of the body (except fat tissue, as alcohol cannot dissolve in fat). Once inside the tissues, alcohol exerts its effects on the body. The observed effects depend directly on the blood alcohol concentration (BAC), which is related to the amount of alcohol the person has consumed. A person's BAC can rise significantly within 20 minutes after having a drink.