The discrepancy between breast cancer risk and alcohol consumption has been frequently questioned, given that patients who consumed only red wine in studies on alcohol appeared to have a decreased risk of the disease.
According to a team from Boston University, the science behind this seems to appear straightforward.
A compound in red wine that belongs to the family of molecules known as aromatase inhibitors prevents the natural transformation of testosterone into estrogen, and results in lowered levels of estrogen.
The study found that similar to prescriptions given to breast cancer patients of aromatase inhibitors such as Arimidex (anastrozole), Aromasin (exemestane), and Femara (letrozole), the natural aromatase inhibitors found in red wine appear to lower levels of hormones and associated proteins in the blood.
The results held up when contrasted against consumption of white wine, which did not change hormone levels.
The link between estrogen exposure and breast cancer is not extremely well understood, but high levels of estrogen without an accompanying rise in progesterone levels has been linked to an increased risk of developing breast cancer.
The study contrasted a group of 36 women who were given white wine to drink for a month, then switched to a month of red wine with regular blood samples taken for analysis throughout the study.
Hormone levels including estrogen, testosterone and their associated proteins in the blood were evaluated for comparison.
Commentary from peer reviewers at Boston University included the caveat that the results do not conclusively prove anything, that similar studies had not found this link, and that another family of compounds called polyphenols in red wine may also explain the protective effect against breast cancer.
The results were published in the Journal of Women’s Health.
The authors of this research denied any financial conflict of interest.
In the United States, one out of every eight women will be diagnosed with breast cancer sometime in her life. In 2010, there were over 250,000 new cases of breast cancer in women, and the number is rising. While treatment is improving, almost 40,000 women still died from breast cancer during 2009. However, there are still 2.5 million women in the US who are survivors.
Breast cancer, like any other cancer, is malignant, uncontrolled growth of breast tissue, usually from the tissue that lines the milk ducts (ductal carcinoma) or the tissue that makes the milk (lobular carcinoma). When cancer has not invaded other parts of the breast, it is referred to as in situ. (ex. Ductal carcinoma in situ). Breast cancers are also defined by their genes and hormone sensitivity. Some grow in response to the presence of estrogen, and area called ER+. Others have specific genes that make the cancer more aggressive, such as the gene HER2. These are important distinctions that direct treatment and prognosis.