A man drinks a glass of whiskey. Image by Tim Sandle.
A genetic study has provided new evidence that alcohol accelerates biological aging. This is based on experimental evidence that participants who recorded higher weekly doses of alcohol were found to have significantly shorter telomeres. This indicates direct DNA damage.
In more extreme cases of alcohol use, it has been found Oxford University researchers that alcohol use disorder was associated with age-related DNA damage before age six. Overall, the results may point to a link between alcohol and age-related diseases such as Alzheimer’s.
While the short-term harm that excessive drinking causes is well known. However, data on whether alcohol accelerates the aging process is less precise. One reason for this is that aging may be related to other factors such as socioeconomic status.
These other variables were controlled thanks to new research which uses genetic analysis. This study showed that alcohol directly accelerates aging by damaging DNA in telomeres.
Telomeres are repetitive DNA sequences that cover the ends of chromosomes and protect them from damage. Telomere length considered an indicator of biological aging, since 50-100 bases of DNA are lost every time a cell replicates. When telomeres become too short, cells can no longer divide and may even die.
Shorter telomere lengths are associated with other diseases associated with aging, such as Alzheimer’s disease, cancer, and coronary heart disease.
The relationship between alcohol consumption and telomere length was studied in 245,000 participants based on data from the UK Biobank. BUT genetic method is called Mendelian randomization (MR) was deployed, in which “genetic proxies” were used to predict the level of exposure for each participant. These were genetic variants that had previously been associated with alcohol use and alcohol use disorders in large-scale, genome-wide association studies.
The researchers also conducted an observational assessment based on participants’ weekly alcohol consumption, which they self-reported at recruitment.
The data showed that there was a significant association between high alcohol consumption and shorter telomeres. For example, compared with drinking less than 6 units of alcohol per week (about two large 250 ml glasses of wine), drinking more than 29 units per week (about ten 250 ml glasses of 14% alcohol by volume) was associated with one to two years of age-related change in telomere length.
In the second example, an increase from 10 units to 32 units per week was associated with the equivalent of 3 years of aging. The association between genetically predictable alcohol consumption and telomere length was only significant for those who drank more than 17 units per week. This suggests that minimal amounts of alcohol may be needed to damage telomeres.
People with alcohol use disorder had significantly shorter telomeres compared to controls. This was equivalent to age changes between 3 and 6 years.
Study appears in a magazine Molecular Psychiatry. The study is titled “Alcohol Consumption and Telomere Length: Mendelian Randomization Clarifies the Effects of Alcohol.”