How Alcohol Damages DNA and Causes Cancer Has Been Demonstrated

Alcohol consumption is one of the most important factors increasing cancer risk. Previous population-based (epidemiological) and laboratory studies had established an association between cancer and alcohol consumption. However, the underlying biological mechanisms had not been clarified. In January 2018, Naturepublished a study showing that alcohol causes cancer by inflicting irreversible DNA damage on blood stem cells.

The research was conducted at the University of Cambridge in the United Kingdom. Specially prepared mouse models were used. Researchers gave mice specific amounts of alcohol or ethanol and attempted to identify the resulting damage to their genes. Advanced genetic technologies were used to perform chromosome analyses and whole-genome sequencing .

DNA analyses used blood stem cells because stem cells have the capacity to spread DNA damage throughout the body. Blood stem cells can also be produced easily.

According to the research results, alcohol causes substantial DNA damage in blood stem cells.

How Does Alcohol Cause DNA Damage?

When alcohol enters cells, a special enzyme converts it into acetaldehyde. Acetaldehyde is a highly toxic/harmful molecule. It causes chromosome abnormalities and breaks in DNA and is a group 1 carcinogenfor humans. Cancer is caused by the accumulation of DNA damage triggering abnormal cell proliferation.

• WHAT IS CANCER? Why and how does it develop? The entire process in brief!

The study examined the defense mechanisms the body has developed against alcohol. The first defense system converts acetaldehyde into a molecule called acetate. Acetate is used in energy production. However, some people have, in the enzyme performing this task (ALDH2), a mutation . As a result, acetaldehyde begins to accumulate substantially, increasing cancer risk. On the other hand, even if your ALDH2 enzyme works properly, heavy alcohol consumption exceeds the enzyme’s capacity, and toxic acetaldehyde still accumulates.

Approximately 540 million people in Asia carry a mutation in the ALDH2 gene. In other words, these people cannot convert acetaldehyde into a harmless molecule. Consequently, their risk of esophageal (food pipe) cancer is very high.

The second defense mechanism is repairing DNA damage. Unfortunately, each person’s DNA repair capacity is not the same.

In mice in which both defense systems were blocked, very extensive alcohol-related DNA damage was observed, and the mice could not produce blood for 10 days.

In Conclusion, Alcohol-Related Cancer Risk Is Substantially Increased in People with Problems in Alcohol Detoxification and DNA Repair Systems.

What Does This Study Mean for Us?

• We now have strong evidence that alcohol increases cancer risk through DNA damage.
• Acetaldehyde had been shown to cause DNA damage in laboratory cell culture models. However, this study is important because it demonstrates the effect of alcohol on DNA in a living organism for the first time.
• Research conducted to date has found that even small amounts of alcohol consumption increase the risk of breast, colorectal, esophageal, laryngeal (voice box) and oral (mouth) cancers. According to a report by the Centers for Disease Control in America, alcohol consumption is not recommended when breast and liver cancer risk is considered.
• The research demonstrated these findings in mouse models using advanced genetic technologies. Further studies can clearly establish the effects in humans. It is important to emphasize that very strong evidence links alcohol with increased cancer risk. To protect yourself against cancer, you should have a healthy lifestyle.
• Which cancer risks does drinking alcohol increase, and by how much?