Lutein is a natural food pigment found in dark green leafy vegetables and egg yolks. Although it is not a nutrient, lutein is an antioxidant, which means that, like some nutrients, it protects cells against oxidative damage linked to symptoms of aging and the development of chronic disease. In your body, lutein is concentrated in the retina and lens of your eye. As a result, much of the research into lutein's role in maintaining good health is focused on prevention and treatment of eye diseases.
Sources
Lutein is a member of the carotenoid family of pigments found in green and yellow-orange foods. It is often discussed in association with zeaxanthin, another pigmented antioxidant found in the same foods and stored in the eye. High concentrations of lutein and zeaxanthin are found in egg yolks and in a wide variety of vegetables, especially dark green, leafy vegetables such as spinach, kale, collards, turnip greens and mustard greens. Significant amounts of lutein are also found in broccoli, Brussels sprouts, green peas, parsley, romaine lettuce, summer squash, scallions, corn and pumpkin.
Function
Lutein protects the eye both from oxidative damage and from the blue radiation component of sunlight. According to Pennington Biomedical Research Center, numerous studies have tried to determine links between blood levels of lutein and the development of various types of cancer, heart disease and stroke, but the associations are not as clear for these conditions as for diseases of the eye.
Role in Eye Disease
Damage from oxidation and light are responsible, in part, for the progression of some eye diseases, including age-related macular degeneration, the most common cause of vision loss and irreversible blindness in older Americans. A study published in a 2008 issue of "Ophthalmology" found that participants with a higher dietary intake of lutein had a lower risk of developing age-related macular degeneration. In a review study published in a 2010 issue of "Current Opinion in Ophthalmology," Duke Eye Center researchers maintained that lutein, along with other antioxidants, is linked to a lower incidence of cataracts, but there is no solid evidence that lutein supplements prevent this disease.
Supplements
Although not much is known about the role of lutein supplements in nutrition or eye care, the Council for Responsible Nutrition published a statement in a 2006 issue of "Regulatory Toxicology and Pharmacology" noting the strong evidence that lutein supplements are safe in doses of up to 20 mg per day. If you are considering taking lutein supplements for any reason, first discuss their usefulness and safety with your physician.
References
- Pennington Biomedical Research Center: Lutein
- ScienceDirect.com: Risk Assessment for the Carotenoids Lutein and Lycopene
- PubMed.gov: Dietary Antioxidants and the Long-Term Incidence of Age-Related Macular Degeneration
- PubMed.gov: Cataracts--We Have Perfected the Surgery, But Is It Time for Prevention?
