Alcohol and cancer
Researchers at the University of Minnesota, working under the guidance of Dr. Silvia Balbo, found in experiments with volunteers that acetaldehyde formed in the body after drinking alcoholic beverages causes serious DNA damage.
Acetaldehyde is one of the products of the breakdown of ethyl alcohol in the human body. The chemical structure of these compounds is close to formaldehyde, known as a strong carcinogen. Earlier laboratory experiments have shown that acetaldehyde is capable of causing DNA damage and the appearance of chromosomal abnormalities in cell cultures, and is also a carcinogen for animal models.
To test the hypothesis about the carcinogenicity of acetaldehyde for humans, the authors once a week for three weeks gave 10 volunteers different doses of vodka corresponding to one, two or three "drinks". "Drink" is a unit of measurement of alcohol consumed and corresponds to 18 ml of pure ethanol, or about 330 ml of beer, 120 ml of wine or 40 ml of spirits.
The study of the material obtained from the participants of the experiments showed that within a few hours after consuming any dose of alcohol in the cells of the oral mucosa of the participants there was a 100-fold increase in the number of DNA complexes with acetaldehyde or so-called DNA adducts. Their content decreased to normal values only after 24 hours. The levels of such DNA adducts in blood cells also increased after drinking alcohol. The danger of DNA adducts is that the changes in gene activity caused by them increase the risk of cell malignancy.
The authors note that the human body has very effective mechanisms for repairing such DNA damage. Therefore, cancer is a very unlikely outcome of so-called "social" alcohol consumption. In addition, the enzyme alcohol dehydrogenase is produced in the body of most people, which quickly converts acetaldehyde into acetic acid – a relatively harmless substance.
However, the results obtained are of great importance for certain ethnic groups. So about 30% of people of Asian origin (about 1.6 billion people worldwide) have a variant of the alcohol dehydrogenase gene, the protein product of which is not able to break down alcohol to acetate. The presence of this gene variant is associated with an increased risk of esophageal cancer when drinking alcohol. The indigenous people of America and Alaska are characterized by the insufficiency of the same enzyme.
The results of the study were presented at the Congress of the American Chemical Society, held on August 19-23 in Philadelphia, Pennsylvania.
Evgeniya Ryabtseva
Portal "Eternal youth" http://vechnayamolodost.ru based on ACS materials:
First evidence from humans on how alcohol may boost risk of cancer.
28.08.2012