The science behind how alcohol increases cancer risk
Global research analysis conducted by the World Cancer Research Fund International shows that alcohol use is linked to an increased risk of seven types of cancers:
- Food pipe,
- Voice box,
- Breast (women),
- Bowel and
- Liver cancer.
Cancer kills ca. 8 million people worldwide every year. The IARC estimates that alcohol lies behind 8% of all cases of cancer. After tobacco (18%), alcohol is thus the second biggest cause of cancer.
But how does alcohol interact with the human body to cause cancer?
Researchers have identified multiple ways that alcohol may increase the risk of cancer, including:
- Metabolizing (breaking down) ethanol in alcoholic drinks to acetaldehyde, which is a toxic chemical and a probable human carcinogen; acetaldehyde can damage both DNA and proteins.
- Generating reactive oxygen species (chemically reactive molecules that contain oxygen), which can damage DNA, proteins, and lipids (fats) through a process called oxidation.
- Impairing the body’s ability to break down and absorb a variety of nutrients that may be associated with cancer risk, including vitamin A; nutrients in the vitamin B complex, such as folate; vitamin C; vitamin D; vitamin E; and carotenoids.
- Increasing blood levels of estrogen, a sex hormone linked to the risk of breast cancer.
Alcoholic beverages may also contain a variety of carcinogenic contaminants that are introduced during fermentation and production, such as nitrosamines, asbestos fibers, phenols, and hydrocarbons.
Understanding the science through an awesome blog
Lucy Eccles of the World Cancer Research Fund has written an interesting blog article about some of the theories of how alcohol causes cancer in the human body. It’s a great read explaining some of the above points easily and pointedly.
Mz Eccles explains how alcohol is converted to a toxic substance that damages DNA. She also makes it more understandable how alcohol can reduce folate absorption and why that is a problem. And she provides understanding of how alcohol causes more dangerous molecules to enter into cells.