Lutein and zeaxanthin, the carotenoids (antioxidants) found in fruits, vegetables and many eye health supplements, may be linked to an increased risk of heart attack, according to a study in Julys Journal of Nutrition.
Lutein and zeaxanthin are found in the macula of the eye, where they filter blue light and protect tissue from the effects of lipid oxidation. Supplements containing lutein and zeaxanthin are thought to reduce the risk of age-related macular degeneration (AMD) and cataract.
In the study, researchers measured the carotenoids and tocopherols in the adipose tissue of 1,456 random patients who experienced a heart attack. Subjects then completed a food frequency questionnaire so researchers could assess their dietary intake of carotenoids.
Subjects were then divided into groups based on their intake or adipose tissue concentrations of carotenoids and tocopherols. Researchers found a relationship between the level of lutein and zeaxanthin in the adipose tissue and diet and the risk for heart attack. The mechanism underlying the positive association between lutein and zeaxanthin and the risk for myocardial infarction [heart attack] warrants investigation, the researchers say.
So, should you stop recommending lutein and zeaxanthin supplementation to patients at risk for AMD and cataract? No, says optometrist Christopher Lievens, of Memphis, Tenn. The effect of antioxidant supplementation on eye disease was evaluated by the Age-Related Eye Disease Study (AREDS), a high-volume, multi-center, prospective clinical trial, he says. The formulation used in this study did not include lutein or zeaxanthin, so the specific effects of these two supplements are uncertain. Although questions about lutein and zeaxanthin now need answers, doctors can still trust the results of AREDS, which recommends high-dose antioxidant supplementation for non-smokers who have intermediate to advanced macular degeneration, he says.
Fruits, Veggies and Red Wine Can Reduce Cataract Risk 1. Christen WG, Liu S, Schaumberg DA, Buring JE. Fruit and vegetable intake and the risk of cataract in women. Am J Clin Nutr 2005 Jun;81(6):1417-22. |