A new study shows that people who consume moderate amounts of red wine or other alcoholic drinks are less likely to develop cataracts, compared to non-drinkers.
People who consume low to moderate levels of alcohol experience a lower incidence of cataracts, compared to people who don’t consume alcohol. These are the findings of a new study evaluating the link between alcohol consumption and the incidence of cataracts.
While the study does not delve into the potential mechanisms involved, their results support a significant association between alcohol consumption and lower incidence of cataracts, when compared to non-drinkers.
What are cataracts?
Each of our eyes contains a small lens, in charge of re-directing light from the outside world into the retina, a light-sensitive layer of tissue containing photoreceptors, which turn light into electrical signals.
In people with cataracts, this lens becomes cloudy over time, due to the breakdown of proteins within the lens, increasingly affecting vision as they age. The condition is painless and in its early stages does not show any symptoms. However, it progresses to the point of affecting vision significantly, with symptoms like blurred vision, sensitivity to light and glare, difficulty reading, and even blindness, among other vision-related problems.
Worldwide, cataracts stand as the most common cause of blindness and visual impairment, typically associated with aging. According to figures from the World Health Organisation about 94 million people are affected by this condition, worldwide. In Australia, more than 400,00 Australians had cataracts in 2017-18, according to data from the Australian Institute of Health and Welfare.
In most cases, the condition can be addressed through surgical removal of the cloudy lens, which is replaced by clear synthetic lens. However, in many parts of the world, where such procedure is not feasible, cataracts lead to vision impairment and blindness. According to a recent report published in The Lancet, cataracts were the leading cause of blindness among adults who were 50 years of age or older in 2020, affecting 15.2 million people.
About this study
The new report, led by Dr Anthony P. Khawaja, from the NIHR Biomedical Research Centre, analysed a massive dataset from the United Kingdom, including 469,387 participants of the UK Biobank, aged around 56 years in average, and 23,162 participants of the EPIC-Norfolk study, aged of 59 years, in average. At the start of these studies, back in 1993 for the EPIC-Norfolk study and 2010 for the UK Biobank cohort, participants answered a detailed questionnaire about their lifestyle, including the amount and type of alcohol they consumed. The participants from the UK Biobank and EPIC-Norfolk studies have been followed up throughout their lifetime by researchers, assessing different aspects of their health.
Now, in their new report, Dr Khawaja used this massive dataset to analyse how different lifestyle factors may have influenced the development of cataracts among participants.
After taking into account factors like age, sex, ethnicity, social deprivation, weight, smoking and diabetes, researchers found that people who consumed 6.5 standard glasses of wine per week were less likely to require cataract surgery.
“There was evidence for reducing the chance of requiring future cataract surgery with progressively higher alcohol intake, but only up to moderate levels within current guidelines,” said lead researcher Dr Khawaja in a press release.
“Participants who consumed alcohol up to 4 times a week were at lower risk than those who consumed 3 times or less per month. But participants who reported daily or almost daily intake were at a similar risk to those who consumed least frequently,” Dr Khawaja told Medical Forum.
The study also found significant differences in the type of alcohol consumed. For example, consuming red wine seemed to have the strongest effect, leading to a 14% lower risk of cataracts. In contrast, drinking white wine / champagne, resulted in a 10% lower risk and beers or spirits led to 13% and 14% lower risk, respectively. However, those who consumed beer and spirits on a daily basis had no reduction in cataract risk.
These finding are consistent with previous studies suggesting that following a diet rich in antioxidants may delay the onset of cataracts. “Cataract development may be due to gradual damage from oxidative stress during aging,” explained Sharon Chua, lead author of the study in a press release. “The fact that our findings were particularly evident in wine drinkers may suggest a protective role of polyphenol antioxidants, which are especially abundant in red wine,” she added.
While this new study found a significant correlation between wine and alcohol consumption with the prevention of cataracts, the authors warn about the risks of excessive alcohol consumption, which is linked to multiple chronic conditions.
Now, Dr Khawaja and his team plans to further explore the link between alcohol consumption and vision problems. “We remain interested in the potential effects of alcohol intake on the eyes and vision. Next, we are examining the potential role of alcohol intake on glaucoma risk,” Dr Khawaja told Medical Forum.
Further studies may also elucidate the potential mechanisms explaining the link between alcohol and cataracts.