Alcohol Absorption and Metabolism

When alcohol is first consumed, it passes down the esophagus through the stomach and into the small intestine. Only a small amount of alcohol is absorbed into the bloodstream through the mucous membrane, the vast majority of alcohol enters the bloodstream through the walls of the small intestine. Alcohol is highly water soluble and the bloodstream rapidly transports the ethanol throughout the body where it is absorbed into the body tissues in proportion to their water content.

Metabolism is the body’s process of converting ingested substances to other compounds. Metabolism involves a number of processes, one of which is referred to as oxidation. Through oxidation in the liver, alcohol is detoxified and removed from the blood through breath, in the sweat and in urine, preventing the alcohol from accumulating and destroying cells and organs. Until all the alcohol consumed has been metabolised, it is distributed throughout the body, affecting the brain and other tissues.

The rate of alcohol metabolism depends, in part, on the amount of metabolising enzymes in the liver, which varies among individuals. In general, after the consumption of one standard drink, the amount of alcohol in the drinker’s blood peaks within 30 to 45 minutes. A standard drink is defined as 330ml of 4% beer, a 100ml glass of wine, or a 30ml glass of straight spirits. Alcohol is metabolized more slowly than it is absorbed. Since the metabolism of alcohol is slow, consumption needs to be controlled to prevent accumulation in the body and intoxication.