Featured Research

from universities, journals, and other organizations

Sunlight Exposure Plus Low Antioxidant Levels May Place Older Adults At Risk For Eye Disease

Date:
October 19, 2008
Source:
London School of Hygiene & Tropical Medicine (LSHTM)
Summary:
People who lack essential antioxidants, and who have high levels of sunlight exposure, have a higher risk of developing advanced macular degeneration (AMD), according to a new study. AMD is a leading cause of poor vision.

People who lack essential antioxidants, and who have high levels of sunlight exposure, have a higher risk of developing advanced macular degeneration (AMD), according to a study published today in the journal Archives of Ophthalmology. AMD is the leading cause of poor vision in the UK.

Related Articles


The EUREYE study, led by Astrid Fletcher, Professor of Epidemiology of Ageing at the London School of Hygiene & Tropical Medicine, is the first to report in human populations an adverse association between sunlight exposure and AMD in people with low levels of antioxidants. It is also unprecedented in the level of detail the researchers used, taking into account not only lifestyle and medical factors but even going so far as to estimate levels of cloud cover in each of the countries from which participants were recruited.

The eye is particularly vulnerable to the damaging effects of sunlight. Ultraviolet radiation is absorbed by the lens, but visible or “blue” light penetrates to the retina so allowing us to see. Protection against the harmful effects of blue light is provided by the antioxidant vitamins C and E, the carotenoids (lutein and zeaxanthin) which filter blue light, and zinc.

Animal and laboratory studies have previously shown that blue light may be a factor in the pathogenesis of AMD, but results have been inconsistent in the few studies that have investigated associations between sunlight exposure and AMD in human populations. Little attention has been paid to the possible interactions between antioxidant levels and light exposure, although it is thought that the adverse effects of sunlight may be mitigated by the protective effects of antioxidants.

4,753 participants aged 65 years were selected randomly in seven centres, Bergen in Norway, Tallinn in Estonia, Belfast in the UK, Paris-Creteil in France, Verona in Italy, Thessaloniki in Greece and Alicante in Spain. The average age of participants was 73.2 and 55% were women. Blue light exposures tended to be higher in participants from centres in southern Europe while participants in an exclusively urban centre (Paris) had the lowest exposures.

Participants underwent fundus photography, and gave a blood sample for antioxidant analysis. They completed a residence and job history in advance, and attended a face-to-face interview. They were asked about their education, smoking and alcohol use, medical history, lifetime residence and level of sunlight exposure, including how much time they had spent outdoors between the hours of 9am and 5pm, and 11am and 3pm each day since they left school and throughout their working life.

Information was collected separately for summer and winter, and for different occupational time periods (including time spent looking after the home) and in retirement up to their current age. For each period, they were asked about their use of eyewear (glasses, contact lenses and sunglasses). The information on sunlight exposure and area of residence was sent to the University of East Anglia and combined with metrological information to estimate lifetime blue light exposure for each participant.

The results indicated that those with the lowest levels of antioxidants were most at risk of AMD due to blue light. In particular, the combination of blue light exposure and low levels of zeaxanthin, alpha tocopherol and Vitamin C was associated with a nearly four-fold likelihood of developing AMD. The researchers found that the associations of blue light in those with low antioxidant status appeared stronger at older ages, reaching a peak at 50-59 years.

The combination of blue light exposure and low concentrations of antioxidants in the blood was also found to be associated with the early stages of AMD, which are common in the population, and that exposures in middle age might be more damaging than at younger ages.

Professor Fletcher comments: ‘In the absence of cost-effective screening methods to identify people in the population with early AMD, we suggest that recommendations on protecting the eyes, ensuring that diets contain the right nutrients and antioxidants, are targeted at the general population, and especially middle-aged people’.

‘We are not telling people to stay out of the sun altogether. The benefits of sunlight are well documented, in particular its role in vitamin D synthesis. But if people want to avoid macular degeneration as they get older, they should avoid exposing their eyes to too much sunlight when they are outside, and take simple precautions, such as wearing a wide-brimmed hat and sunglasses.

‘Nor are we recommending that people should take vitamin supplements. It is perfectly possible to achieve the recommended dietary reference intakes for these essential antioxidants by following a balanced diet’.


Story Source:

The above story is based on materials provided by London School of Hygiene & Tropical Medicine (LSHTM). Note: Materials may be edited for content and length.


Journal Reference:

  1. Fletcher et al. Sunlight Exposure, Antioxidants, and Age-Related Macular Degeneration. Archives of Ophthalmology, 2008; 126 (10): 1396 DOI: 10.1001/archopht.126.10.1396

Cite This Page:

London School of Hygiene & Tropical Medicine (LSHTM). "Sunlight Exposure Plus Low Antioxidant Levels May Place Older Adults At Risk For Eye Disease." ScienceDaily. ScienceDaily, 19 October 2008. <www.sciencedaily.com/releases/2008/10/081013171431.htm>.
London School of Hygiene & Tropical Medicine (LSHTM). (2008, October 19). Sunlight Exposure Plus Low Antioxidant Levels May Place Older Adults At Risk For Eye Disease. ScienceDaily. Retrieved December 20, 2014 from www.sciencedaily.com/releases/2008/10/081013171431.htm
London School of Hygiene & Tropical Medicine (LSHTM). "Sunlight Exposure Plus Low Antioxidant Levels May Place Older Adults At Risk For Eye Disease." ScienceDaily. www.sciencedaily.com/releases/2008/10/081013171431.htm (accessed December 20, 2014).

Share This


More From ScienceDaily



More Health & Medicine News

Saturday, December 20, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

The Best Tips to Curb Holiday Carbs

The Best Tips to Curb Holiday Carbs

Buzz60 (Dec. 19, 2014) It's hard to resist those delicious but fattening carbs we all crave during the winter months, but there are some ways to stay satisfied without consuming the extra calories. Vanessa Freeman (@VanessaFreeTV) has the details. Video provided by Buzz60
Powered by NewsLook.com
Sierra Leone Bikers Spread the Message to Fight Ebola

Sierra Leone Bikers Spread the Message to Fight Ebola

AFP (Dec. 19, 2014) More than 100 motorcyclists hit the road to spread awareness messages about Ebola. Nearly 7,000 people have now died from the virus, almost all of them in west Africa, according to the World Health Organization. Video provided by AFP
Powered by NewsLook.com
Researchers Test Colombian Village With High Alzheimer's Rates

Researchers Test Colombian Village With High Alzheimer's Rates

AFP (Dec. 19, 2014) In Yarumal, a village in N. Colombia, Alzheimer's has ravaged a disproportionately large number of families. A genetic "curse" that may pave the way for research on how to treat the disease that claims a new victim every four seconds. Duration: 02:42 Video provided by AFP
Powered by NewsLook.com
The Best Protein-Filled Foods to Energize You for the New Year

The Best Protein-Filled Foods to Energize You for the New Year

Buzz60 (Dec. 19, 2014) The new year is coming and nothing will energize you more for 2015 than protein-filled foods. Fitness and nutrition expert John Basedow (@JohnBasedow) gives his favorite high protein foods that will help you build muscle, lose fat and have endless energy. Video provided by Buzz60
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:

Strange & Offbeat Stories


Health & Medicine

Mind & Brain

Living & Well

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins