Study finds regular exercise reduces risk of age-related cataracts

Regular physical activity could help to reduce the risk of age-related cataracts (ARC), a new study has revealed, with researchers encouraging people to boost their exercise regime to help prevent a reduction in vision.

The research, carried out by Xi’an Jiaotong University and the University of South Australia (UniSA), analysed data from six different studies looking at how exercise reduced oxidative damage in the eye – and the results were positive. Researchers found a 10 per cent reduction in age-related cataracts among people who engaged in regular physical activity, with walking and cycling highlighted as the most beneficial forms of exercise.

Age-related cataracts are one of the most common causes of vision impairment and blindness in the world, with more than 1.5 million Australian aged 55-plus living with the condition. Having a cataract or cataracts (they can appear in one or both eyes) is often compared to looking through a foggy window, with the most common symptoms of cataracts being blurred vision, sensitivity to light and poor night vision.

Unfortunately, it’s considered a natural part of ageing and although surgery is an effective option to recover vision, it’s very costly. Thankfully though, according to UniSA epidemiologist Dr Ming Li, physical activity reduces stress in the eye which impacts the level of cell damage and hence reduces the likeliness of developing cataracts.

Previous studies have also shown that long-term physical activity also elevates HDL (high-density lipoprotein), also known as the ‘good cholesterol’, which may carry more antioxidants from plasma to the lens to prevent oxidative damage. While exercise is known to improve insulin resistance and lipid profiles, both of which have been associated which have been associated with an increased risk of ARC.

“The lens is highly susceptible to oxidative damage because of its high concentration of polyunsaturated fatty acid and its specific biological function,” Li said. “Although we don’t completely understand the mechanisms underlying ARC, we do know that ageing and oxidative damage play a crucial role in the development of the disease.”

The researchers found that the risk of developing cataracts could potentially decrease by two per cent for every hour of cycling or walking per day. While Li said exercise increases antioxidant enzyme activity which has all sorts of benefits, including limiting infections and inflammation in the eye.

“Considering the fact that 24 per cent of adults are inactive, these findings will hopefully encourage older people to start exercising on a regular basis,” she said.