Alcohol Boosts Breast Cancer Risk
Alcohol is the common shorthand for a substance known chemically as ethyl alcohol or ethanol. Inside the body, it produces inebriation by altering the levels of vital chemicals in the brain and depressing the normal rate of activity in the central nervous system. As the word intoxication implies, alcohol acts as a toxin. Its presence degrades normal function in a wide variety of cells and stops organs throughout the body from performing up to their normal health-sustaining standards.
Breast Cancer Basics
In the majority of cases, cancerous changes first appear in the ducts (tubes) that allow breast milk to flow from the milk-producing lobes in the breasts' interiors to the nipples; doctors call this type of cancer ductal carcinoma. In most other cases, cancerous changes first appear in the lobes themselves; doctors call this type of cancer lobular carcinoma. In addition, a small minority of cancers originate in other breast regions. Cancer that has not spread from its origin point to other breast tissues is known as noninvasive or "in situ" breast cancer. Doctors refer to cancers that have spread to other breast tissues as invasive cancer. While men sometimes develop breast cancer, the vast majority of cases appear in women.
Alcohol's Cancerous Effects
Ethyl alcohol is officially listed as a known carcinogen by the U.S. Department of Health and Human Services. However, when it comes to breast cancer, for a long time, doctors and researchers had no clear idea how alcohol triggered its carcinogenic effects on healthy cells. According to research presented in 2012 to the American Society for Biochemistry and Molecular Biology, it seems that alcohol does not directly produce cancerous changes in breast tissue. Instead, the damage apparently occurs when a protein inside breast cells, called CYP2E1, tries to protect these cells from ethyl alcohol by breaking it down and rendering it inactive. Unfortunately, when CYP2E1 performs this job, it also releases substances called free radicals, which can damage or kill cells by altering their DNA coding. In turn, these DNA changes can lead to the growth of malignant, cancer-causing cells within breast tissue.
The levels of CYP2E1 in breast tissue vary from person to person. People with relatively high levels of the protein in their breasts typically experience a larger alcohol-related accumulation of harmful free radicals than people with relatively low levels of the protein in their breasts. Although no one is quite sure, this may mean that people with high CYP2E1 levels who drink significant amounts of alcohol have increased breast cancer risks when compared to people with low CYP2E1 levels who drink similar amounts of alcohol.
The risk for alcohol-related breast cancer increases with the amount of alcohol consumed on a regular basis. However, several factors can alter this relatively simple correlation. For instance, breast cancer has a number of additional known risk factors - including genetic heritage, age, and childbirth history - that may play a bigger role in cancer development than alcohol consumption. Also, people with unusually high levels of CYP2E1 in their bodies may have heightened breast cancer risks even at relatively low levels of alcohol intake.
Further making the link between alcohol consumption and breast cancer, a long-term study by Harvard Medical School published in 2011 found that moderate alcohol consumption could potentially elevate the risk for breast cancer in anyone, regardless of other factors.