‘Sunlight–lower antioxidants level’ duo more likely to damage vision

London, October 15: Researchers of a new study have found that the combination of low antioxidant levels and exposure to sunlight may make one susceptible to a common vision-damaging disease called age-related macular degeneration (AMD).

Though the condition is usually seen in older adults, the damage can start decades before, researchers have warned.

As the retina, the inner layer of the eye which contains nerves that communicate sight, is vulnerable to the damaging effects of light, the antioxidant enzymes including vitamins C and E, the carotenoids (lutein and zeaxanthin) and zinc act as a shield and protect against the harmful effects of blue light on the retina, researchers explain.

For the study, experts from the London School of Hygiene and Tropical Medicine in the UK monitored over 4,500 older adults with an average age of 73.2 years. Hailing from seven European countries, the participants had already participated in the European Eye Study.

Participants’ eyes were checked for cases of AMD and blood samples were collected to measure antioxidant concentrations. They were also interviewed for their lifetime sunlight exposure.

In-depth analysis revealed that for participants with relatively low antioxidant levels, sun exposure was linked to an increased risk of advanced AMD. However, no such link was seen in people who recorded high on blood antioxidant levels.

Moreover, in participants with the lowest levels of blood antioxidantsdefine, every unit increase in sunlight exposure increased their risk of developing AMD by 40 percent.

Conversely, a daily intake of diet rich in beta-carotene, vitamin C, vitamin E, and zinc and cutting out on sunlight exposure can reduce the risk of progressing from early to advanced AMD by about 25 percent, the researchers tout.

Advising to act cautiously, Astrid E. Fletcher, lead author of the study said, “We recommend that people use eye protection, including sunglasses and wide-brimmed hats, if going outside and especially in bright sunlight".

"Our advice on nutrition," she added, "is that people should ensure that they follow the five-a-day recommendations. In particular, they should see that their diet includes leafy green vegetables, citrus fruit, vegetable oils and nuts, as these are good sources of the antioxidant vitamins of relevance to the retina".

The results of the study feature in the October issue of Archives of Ophthalmology.