Blood alcohol content (BAC) is the amount of alcohol per unit of blood in the bloodstream. Alcohol that is consumed is absorbed by the body in the stomach and small intestine and enters the bloodstream. According to the National Traffic Highway Safety Administration, alcohol is absorbed quickly by the body. The blood alcohol content can be measured within 30 to 70 minutes of consumption. Approximately one-half ounce of alcohol can be found in one shot of distilled spirits, one 12-ounce beer or one 5-ounce glass of wine. Different factors affect the body's absorption of the alcohol.
Number of Drinks
The number of alcohol drinks consumed is a factor in blood alcohol content. A higher number of drinks consumed will result in a higher blood alcohol content.
Speed of Drinking
When alcoholic drinks are consumed more quickly, the blood alcohol content will elevate faster. If the same number of drinks is consumed over a shorter and a longer period of time, the drinks consumed over a shorter period of time will reach a higher blood alcohol content than those consumed over the longer period of time. The blood alcohol content does not just elevate more quickly, it reaches a higher level.
When one pound of body weight is compared between men and women, the pound of body weight of women typically have more body fat and less water. Alcohol does not enter fat cells as easily as other types of body cells, and therefore, alcohol tends to remain longer in the bloodstreams of women, which causes them to reach higher blood alcohol contents than men with the same amount of alcohol consumed.
People who weigh more will generally have more water present in their bodies. This water has a dilution effect on alcohol that is consumed, resulting in lower blood alcohol content. If two people consume the same amount of alcohol, the person who weighs more will generally have a lower blood alcohol content if other factors are equal.
Food in the stomach will slow the absorption of consumed alcohol into the bloodstream. This is because a valve at the bottom of the stomach closes after meals so that food can stay in the stomach and be digested. This keeps the consumed alcohol in the stomach, where it is absorbed less efficiently than in the small intestine.