Researchers have used prospectively obtained data from 105,986 women in a comprehensive study to evaluate the moderate consumption of alcohol and breast cancer risk association.
A large amount of observational research has revealed that women who consume alcohol have an increased risk of breast cancer. The relation appears to be generally stronger for those women who binge drink, are also using post-menopausal hormonal therapy, or/and have low dietary folate intake. Most research has shown that heavier drinkers have the highest risk of breast cancer.
A modest increase in breast cancer risk was found to in women who consume alcohol in this study, even those women whose total consumption of alcohol was in the range of 3 – 6 drinks a week. The same small increases of breast cancer risk have been observed from consumption of alcohol in the majority of earlier observational research.
The very large number of subjects was a strength of this current study, and allowed the investigators to try and determine whether both the quantity of alcohol as well as the consumption frequency were important in this association, and strong effects weren’t found for either. After adjusting for the cumulative lifetime of alcohol consumption, there wasn’t any effect of the consumption frequency.
A failure to report on the impact of diet and folate intake on the alcohol and risk of breast cancer association was a weakness in the study. It has previously shown that folate is a potential moderator of the effects of alcohol on the risk of breast cancer.
Women face a dilemma in regard to alcohol intake, which could slightly increase breast cancer risk but significantly decrease the risk of various other common diseases, particularly cardiovascular conditions. The researchers did find a quite small increased risk of breast cancer at low levels of alcohol consumption. Estrogen levels are increased with intake of alcohol and this means that women have a slightly lower osteoporosis risk and a slightly higher breast cancer risk. Although the current data indicate that small to moderate amounts of alcohol offer protection against osteoporosis, cardiovascular disease, vascular dementia, and diabetes mellitus, risk of breast cancer is slightly increased.