Here are the main factors that play a role in women crossing their legal BAC limit faster than men:
Women have a lower percentage of body water compared to men. Higher body water content helps dilute alcohol concentration better. So the BAC levels accumulate much faster in women’s bodies.
Women have lesser Alcohol Dehydrogenase in their stomach linings compared to men. It weakens their ability to metabolize the alcohol while men can do it at a faster pace.
Fluctuations in estrogen levels due to menstrual cycles or medication can also lead to higher BAC levels.