The American publication ‘Nutrition Action’’s most recent article highlights issues about women and alcohol by George Koob (Director of the National Institute on Alcohol Abuse and Alcoholism at the National Institutes of Health), Walter Willet (chair of the Department of Nutrition at the Harvard School of Public Health) and Regina Ziegler (of the Division of Cancer Epidemiology & Genetics at the National Cancer Institute).
The perspectives of these specialists highlight how, although alcohol has adverse effects on both sexes, women are more affected by alcohol due to their physiology. Body water content is naturally higher in males at around 61% compared to that of 52% in females which means a higher concentration of alcohol in their cells compared to men. Therefore, men dilute alcohol more efficiently regardless of weight and height. In addition to this, body fat is related to the absorption of alcohol; fat tissue does not absorb alcohol as well as muscle tissue, and since the concentration of body fat is higher in women than in men, a higher concentration of alcohol remains in their bloodstreams.
Before entering the bloodstream, alcohol which would otherwise be toxic is broken down by dehydrogenase in the stomach. Women have decreased dehydrogenase activity compared to that of men and so they breakdown alcohol more slowly. According to the Institute of Alcohol Studies, the hormonal changes that women experience during or prior to menstruation slows down the rate at which alcohol is metabolised. Women who take birth control pills containing oestrogen may also feel extended effects of intoxication as the medication could increase blood alcohol concentration. In addition to this, the World Cancer Research Fund’s (WCRF) Continuous Update Project (CUP), also reports that alcohol increases the concentration of oestrogen in the bloodstream, hence a chain reaction between oestrogens and alcohol is observed.
Although these physiological differences in women affect blood alcohol concentration, it should also be noted that women are more likely to develop alcohol-related complications sooner than men; including heart complications, liver problems and cancer. In the article published by Nutrition Action, the focus is on the relationship between consumption of alcohol and breast cancer. The risk of premenopausal and postmenopausal breast cancer increases with greater intake of alcohol; the highest risk being in women who started drinking at an earlier age and continued to do so.
It should be noted that it isn’t only high alcohol intake that is related to breast cancer; the WCRF reports in their latest update on the topic from the CUP that a 5% increase in risk of breast cancer in premenopausal women and 9% in postmenopausal women is observed with just 10mg of alcohol per day. This is equivalent to just one small glass of wine and evidently, whether your preference is a vintage Bordeux, a 10 year old Laphroig or supermarket’s own brand vodka, the type of alcohol you drink has no differing consequence in their health effects.
Care must be taken if you choose to drink alcohol; the CMO suggests that the safest amount to consume is no more than 14 units of alcohol per week, spreading this out over several days (and having several alcohol free days each week). To help achieve the CMO guidelines, the WCRF have devised some tips to help you limit your alcohol intake. After all, around 38% of breast cancer cases could be prevented by making healthy lifestyle changes and alcohol accounts for 22% of these.
Read more about the science on alcohol and breast cancer in our blog on breast cancer and lifestyle.