Next time you're browsing the produce aisle, reach for green leafy vegetables. They provide the richest source of lutein, a nutrient belonging to the carotenoid family. Of the 600 carotenoids identified, lutein represents one of only two deposited in high amounts in the retina, the other being zeaxanthin. This light-sensitive area of the eye plays a crucial role in proper vision. Lutein's role in eye health is its most widely recognized, but the nutrient has other benefits as well.
Lutein acts as an antioxidant, protecting your cells from free-radical damage. Think of antioxidants as heroes and free radicals as villains. Free radicals are unstable atoms with one or more unpaired electrons that roam around stealing electrons from nearby molecules. The problem is this theft can damage healthy cells. Antioxidants neutralize free radicals, protecting against potential damage. The idea that free radicals contribute to the degenerative effects of aging is a commonly accepted theory.
Fighting Macular Degeneration
Age-related macular degeneration is an eye disease affecting your central vision. It can cause blurred vision and lead to vision loss. Two types of AMD are classified: dry and wet, often referred to as early and late. About 85 percent of individuals with this condition have dry AMD, according to the University of Maryland Medical Center; however, wet AMD is responsible for 90 percent of severe vision loss from the condition. Evidence suggests a diet rich in lutein helps protect against wet but not dry AMD, according to a systematic review published in the February 2012 issue of the "British Journal of Nutrition."
Protects Against Cataracts
Eating a diet abundant in foods containing high amounts of lutein may protect against age-related cataracts, according to a meta-analysis published in the January 2014 issue of the journal "Graefe's Archives for Clinical and Experimental Ophthalmology." Cataracts are clumps of protein that form on the lens of the eye. They usually develop slowly as you age and can interfere with vision, causing blurriness and cloudiness. The review found especially strong evidence for lutein protecting against nuclear cataracts, which affect the center of the lens.
Getting Your Daily Fill
Lutein is plentiful in green leafy vegetables, such as kale, spinach, collard greens and turnip greens. A recommended intake has not been established, but it's estimated that 5 to 30 milligrams daily provides benefits, according to the New York University Langone Medical Center. You can easily get this amount from your diet. For example, 1 cup of cooked kale contains 23.8 milligrams of lutein, and a cup of cooked spinach contains 20 milligrams. Studies showing the benefit of supplementation are lacking, so focus on dietary intake.
- American Optometric Association: Lutein & Zeaxanthin
- New York University Langone Medical Center: Lutein
- Ohio State University: The Free Radical Theory of Aging
- University of Maryland Medical Center: Macular Degeneration
- British Journal of Nutrition: Lutein and Zeaxanthin Intake and the Risk of Age-Related Macular Degeneration - A Systematic Review and Meta-Analysis
- Graefe's Archives for Clinical and Experimental Ophthalmology: A Dose-Response Meta-Analysis of Dietary Lutein and Zeaxanthin Intake in Relation to Risk of Age-Related Cataract
- University of Maryland Medical Center: Cataracts