According to B.R.A.D., women have less of a metabolizing enzyme, called alcohol dehydrogenase, as compared to men. This enzyme is the primary agent responsible for the ejection of alcohol from the body. As a result, more of what a woman drinks will enter the bloodstream as pure alcohol.
B.R.A.D. also states that women tend to reach higher BAC levels faster than men because they are generally physically smaller than men. Further, women typically carry more body fat than males, and body fat contains little water. As a result, women have less water in their bodies to dilute alcohol. In addition to a higher body fat content, fluctuating hormonal levels in women can also result in women reaching higher BAC levels faster than men.