Males and females differ in their ability to metabolize alcohol. This difference is due to variations in the amount and activity of alcohol dehydrogenase (ADH), the enzyme responsible for metabolizing alcohol.
Males have highly active (i.e., fast) forms of ADH in their stomach and their liver. The presence of ADH in the stomach of males can reduce the absorption of alcohol by 30%! By contrast, females have almost no ADH in their stomach. Consequently, females absorb more alcohol into their bloodstream. Additionally, the ADH in the liver of females is much less active than the ADH in the male liver. Taken together, these gender differences in alcohol metabolism result in increased BACs for females compared to males if they both consume the same amount of alcohol. For the same number of drinks, it is easier for females to become intoxicated (Figure 1.13).
Learn more about the genetic basis for differences in alcohol metabolism.
Figure 1.13 Males metabolize ethanol more efficiently than do females, so they have lower BACs after drinking the same amount of alcohol.
Click here to see a summary of the factors that explain why females have higher BACs compared to males if they drink the same amount of alcohol.