Lutein Benefit for cataract, eye disease, macular degeneration, visual acuity

Numerous studies have shown that lutein and zeaxanthin provide significant benefit and protection against the potential damage caused by light striking macula lutea portion of the retina.
   It is now well known that those with high intakes of fruit and vegetables have a lower risk for coronary disease, stroke, hypertension, obesity, many types of cancer, chronic pulmonary disease, osteoporosis, and various eye disorders, including macular degeneration. Fruits and vegetables have a high content of carotenoids and flavonoids. Lutein is an important carotenoid. Does the benefit of lutein extend beyond vision?

Cataracts
Excessive sunlight exposure increases the risk for cataracts. Vitamin C, lutein, and zeaxanthin offer some protection against cataract formation. Eyesight vision article discusses this in more detail.

Antioxidant
Effect of Spinacia oleraceae L. and Perilla frutescens L. on antioxidants and lipid peroxidation in an intervention study in healthy individuals.
Plant Foods Hum Nutr. 2010; Schirrmacher G, Skurk T, Hauner H. Center of Greenhouses and Laboratories Dürnast, Quality of Vegetal Foodstuff, Life Science Center Weihenstephan, Technische Universität München, Freising, Germany.
To investigate whether the ingestion of preparations from spinach or perilla, two carotenoid-rich leafy vegetables, is followed by an increase in carotenoid concentration and/or affects parameters of oxidative stress in human blood plasma. 12 healthy volunteers ingested a perilla- or spinach preparation for 10 days (5 mg lutein/d). We quantified antioxidant levels in plasma, kinetics of lipid peroxidation, MDA concentration, and total antioxidative capacity of plasma. We observed a significant increase in lutein content and a moderate increase (n.s.) in beta-carotene content in human blood plasma after consumption of spinach or perilla. The markers of lipid peroxidation tended to decrease, but no influence on antioxidative capacity of plasma could be detected. The high lutein content of perilla caused a more pronounced increase of lutein compared to spinach. Both vegetables seem to be able to influence lipid peroxidation in a beneficial manner.

Lutein benefit for cholesterol
Lutein reduces oxidation of LDL-cholesterol.

Esophageal cancer
Lutein inhibits smitosis and stimulates apoptosis of esophageal EC9706 cells in vitro. The apoptotic effect may result from the down-regulation of expression of Bcl-2 and up-regulation expression of Bax.

Heart and cardiovascular system
A meta-analysis of epidemiological studies indicates that high lutein intakes may modestly reduce coronary risk.

Liver cancer
Lutein as a potential agent for liver cancer prevention.

Lutein benefit for macular degeneration
A definite association between lutein and zeaxanthin supplementation and clinical benefit has yet to be shown; however, it may still be an appropriate cautionary measure for patients at high risk for developing age related macular degeneration to supplement with lutein and zeaxathin a few times a week.

Prostate cancer
Epidemiological and laboratory studies indicate that lutein may be beneficial in reducing the risk for prostate cancer.

Lutein protects against sun skin damage
Mice given a diet with lutein and zeaxanthin have less damage to their skin when exposed to UVB light.
   In ultraviolet radiation exposed fibroblasts, lutein improvesd cell viability, membrane integrity and inhibits elastin expression. Lutein also inhibits matrix metalloproteinases MMP to tissue inhibitors of metalloproteinases TIMP ratio in dermal fibroblasts and melanoma cells, inhibits cell loss, reduces membrane damage and elastin expression.