Andrew’s presentation analyzed the social factors that contributed to the phenomenon of women making up 60% of the opium addicts. But there are also biological factors regarding drug effect.
Opium has high lipid solubility, which means it can be absorbed by fat. Cell membranes are constructed by fat, so opium can directly bypass the membranes and get to the bloodstream more rapidly. Females have approximately 10% more body fat than male on average. Therefore, females on average would need more opium intake to get the same effect as males since more opium is stored in the fat cells. This would also contribute to the higher risks of opium addiction among females.