It’s no secret that Americans love to drink; according to one recent report, the average American consumes over two gallons of alcohol each year. Unfortunately, all of that alcohol can be quite harmful to the body. In fact, a new study has found a connection between alcohol intake and cancer risk.

DNA Data

This new study was a collaborative effort, featuring contributors from Oxford Population Health, Peking University and the Chinese Academy of Medical Sciences.

The team directed their focus towards two specific genetic variants, known as alleles. Among Chinese and other East Asian individuals, possessing these alleles reduces a person’s ability to tolerate alcohol. Instead, these variants inhibit enzymes that regulate alcohol detoxification. As a result of this interference, a toxic compound known as acetaldehyde begins to build up within the bloodstream.

The first variant affects an enzyme known as aldehyde dehydrogenase 2 (ALDH2), making this enzyme less effective at its job. In contrast, the second variant causes an enzyme known as alcohol dehydrogenase 1B (ADH1B) to become abnormally active.

The next step was to review DNA samples, for which the team relied upon the China Kadoorie Biobank study. The researchers also reviewed questionnaires from this same source, which had been distributed to participants and completed at routine follow-ups. On average, those in the Biobank study had been tracked for more than a decade on average.

Drink to Good Health?

Below are some of the major findings of the study:

• Not surprisingly, people with the two variants had relatively low levels of alcohol consumption, and tended to drink alcohol less frequently.
• Throughout the study’s followup period, it was determined that 7.4% of the male participants were diagnosed with cancer.
• Cancer was between 13 and 25 percent less likely to develop in male subjects who carried one or two of the low-alcohol tolerability alleles for ADH1B.
• In contrast, alcohol-linked cancer risk was found to be elevated in men who drank despite carrying one copy of the low-alcohol tolerability allele for ALDH2.

In summarizing his team’s work, lead researcher Dr Pek Kei (Becky) Im stated that “these findings indicate that alcohol directly causes several types of cancer, and that these risks may be increased further in people with inherited low alcohol tolerability who cannot properly metabolise alcohol.”

Im’s opinion was echoed by Dr Iona Millwood, who noted that “our study reinforces the need to lower population levels of alcohol consumption for cancer prevention, especially in China where alcohol consumption is increasing despite the low alcohol tolerability among a large subset of the population.”