A woman who consumes plenty of dark leafy vegetables which are rich in lutein and zeaxanthin, as well as sufficient vitamin E from supplements/foods seems to have better protection against developing cataracts, says an article in Archives of Ophthalmology (JAMA/Archives), January issue.
The researchers explain “The oxidative hypothesis of cataract formation posits that reactive oxygen species can damage lens proteins and fiber cell membranes and that nutrients with antioxidant capabilities can protect against these changes.”
It is accurately believed that vitamin E, vitamin C, beta carotene, lutein and zeaxanthin are effective antioxidants. Lutein and zeaxanthin are the only carotenoids that are present in the human eye lens – they may protect us against cataracts by filtering damaging blue light. Carotenoids are natural fat-soluble pigments found in certain plants.
William G. Christen, Sc.D., Brigham & Women’s Hospital and Harvard Medical School, Boston, and team looked at dietary data from 35,551 female health professionals who had taken part in the Women’s Health Study (1993). The women were monitored for 10 years (average). The diets of the women who developed cataracts were compared with the diets of the women who remained cataract-free.
The researchers report that 2,031 women developed cataracts during the ten-year period. They split the women into five groups, depending on how much lutein and zeaxanthin they consumed. They found that –
— Women who consumed about 6,716 micrograms (top group) of lutein and zeaxanthin per day had an 18% lower likelihood of having cataracts, compared to the women who consumed 1,177 micrograms (bottom group) per day.
— The 20% highest consumers of vitamin E from food/supplements, approximately 262.4 milligrams daily, had a 14% lower chance of developing cataracts, compared to the 20% lowest consumers who consumed 4.4 milligrams per day.
The researchers wrote “In conclusion, these prospective data from a large cohort of female health professionals indicate that higher intakes of lutein/zeaxanthin and vitamin E are associated with decreased risk of cataract. Although reliable data from randomized trials are accumulating for vitamin E and other antioxidant vitamins, randomized trial data for lutein/zeaxanthin are lacking. Such information will help to clarify the benefits of supplemental use of lutein/zeaxanthin and provide the most reliable evidence on which to base public health recommendations for cataract prevention by vitamin supplementation.”
“Dietary Carotenoids, Vitamins C and E, and Risk of Cataract in Women – A Prospective Study”
William G. Christen, ScD; Simin Liu, MD; Robert J. Glynn, ScD; J. Michael Gaziano, MD; Julie E. Buring, ScD
Arch Ophthalmol. 2008;126(1):102-109.