Eye Color and Cataract Risk

Why Light-Colored Eyes Are More Vulnerable to Sun Damage

close-up of blue eye

Elton John's song may depict "blue eyes laughing in the sun", but people with fair eyes should better understand the eye risks posed by cumulative ultraviolet light exposure, according to the ​American Academy of Ophthalmology (AAO).  In a 2014 poll commissioned by the AAO, few people with blue, green or hazel eyes seemed to know that their light eye color put them at greater danger of future cataracts and other serious eye problems.

Cataracts and the aging eye:   A natural side effect of aging, a cataract is a progressive clouding of the eye's lens.  While many factors such as smoking and steroid use may play a role in the development of cataracts, they are linked to years of cumulative sun exposure.  More than half of Americans will develop cataracts by the time they reach the age of 80, threatening their eyesight, independence and overall health.

Left untreated, cataracts can result in a complete loss of vision; they are a leading cause of blindness around the world.

Are light or dark eyes more susceptible to cataracts?  People with all eye colors get cataracts, but research has found that adults with light-colored eyes are more vulnerable to all forms of UV damage, including cataracts, uveal or ocular melanoma, and age-related macular degeneration (ARMD).

About half of the North American population has light-colored eyes.

For example, a 2006 review published in the Archives of Ophthalmology examined 132 studies and concluded that people with light eye color had a 75% greater chance of developing ocular melanoma, the most common type of eye cancer and most common location for melanoma besides the skin.

Just as darker skin tones contain pigments which absorb incoming ultraviolet light, dark irises - the colored part of the eye - are believed to prevent more UV rays from hitting and damaging the underlying structures of the eye such as the lens, the retina and the macula.

Conflicting research:  Surprisingly, two Australian studies published in 2000 and 2002 in the American Journal of Ophthalmology found the opposite: dark-eyed adults were 80% more likely to develop cataracts over the 5-year investigation, compared with their blue-eyed counterparts.

Both papers involved the same population of older adults, as part of the Blue Mountains Eye Study.  More than 3,600 men and women between the ages of 49 and 97 took part in the longitudinal research.

Read more: How do scientists find and track all those people?

Why the discrepancy between research results?  Why might dark-eyed subjects suffer more UV damage in the form of cataracts in these studies?  To answer this question, I consulted Stephanie Marioneaux, board-certified ophthalmologist and cornea specialist.

"The Australian studies were well-designed and well-conducted," she observes. "But the data about dark eyes may only tell us about that particular population, and can't necessarily be extrapolated to other geographic areas.

  Australia is an island with a relatively homogeneous population, and there may be genetic or even nutritional risk factors - because we know nutrition can affect eye health - which weren't accounted for in this research."

How do I protect my eyes?  Whether your eyes are light or dark, wearing sunglasses which fully block ultraviolet rays remains the easiest way to protect against sun damage.  Look for "100% UV Protection" (or 99%) on the label to make sure the glasses block both UVA and UVB rays.  Another way broad-spectrum coverage is indicated is "UV400", which means the glasses absorb UV rays up to 400 nanometers.

Make sure you opt for a large frame - ideally in a wrap-around style with broad arms - because UV rays have been shown to sneak in over, under and around glasses frames according to Marioneaux.  Eyes are further protected by wearing a wide-brimmed hat or visor.

Finally, don't stare at the sunset, no matter how beautiful, advises Marioneaux.

"It may not seem bright, but that's a huge dose of sunlight," she cautions.  "Regardless of your eye color, don't rely on your sense of how bright the sun is to tell you whether to wear your sunglasses.  And remember, you can't tell by looking at the glasses whether they offer broad-spectrum coverage.  Make sure you look for this feature on the label when you buy them."

Bottom line:  Sunglasses are an easy and effective way to prevent future sun damage, whether your eyes are blue, brown, or something in between.

Read more about vision and aging:


Age-Related Eye Disease Study Results. US National Institutes of Health National Eye Institute Information Sheet. Accessed May 27, 2014.

Cataract in the Adult Eye Summary Benchmark - 2013. American Academy of Ophthalmology Preferred Practice Guidelines. Accessed May 26, 2014.

Cumming, RG, Mitchell P and Lim R.  "Iris color and cataract: the Blue Mountains Eye Study."  Am J Ophthalmol. 2000 Aug;130(2):237-8.

Ezekiel Weis, Chirag P. Shah, Martin Lajous,  Jerry A. Shields, and Carol L. Shields. "The Association Between Host Susceptibility Factors and Uveal Melanoma: A Meta-analysis." Arch Ophthalmol. 2006;124(1):54-60.

Facts About Cataracts. US National Institutes of Health National Eye Institute Public Information Sheet. Accessed May 28, 2014.

Andrea Schmidt-Pokrzywniak, Karl-Heinz Jöckel, Norbert Bornfeld, Wolfgang Sauerwein, Andreas Stang. "Positive Interaction Between Light Iris Color and Ultraviolet Radiation in Relation to the Risk of Uveal Melanoma: A Case-Control Study." Ophthalmology  February 2009. Vol. 116, Issue 2, Pages 340-348.

Stephanie Marioneaux, Board-certified ophthalmologist and cornea specialist.  Interview conducted by phone May 28, 2104.

Younan C, Mitchell P, Cumming RG, Rochtchina E, Wang JJ. "Iris color and incident cataract and cataract surgery: the Blue Mountains Eye Study." Am J Ophthalmol. 2002 Aug;134(2):273-4.

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