BUFFALO, N.Y.–Antioxidants, specifically the carotenoids lutein and zeaxanthin, may enhance lung function, according to scientists from University at Buffalo whose work will be published in the March 1 issue of the American Journal of Epidemiology (www.aje.oupjournals.org).
According to a study led by Holgar Schunemann, M.D., Ph.D., who is an assistant professor of social and preventive medicine, lutein and zeaxanthin may be more effective in enhancing lung health than other antioxidants.
Based on the previous finding that antioxidants play an important role in many lung diseases, Schunemann and colleagues studied the forced expiratory volume in one second (FEV1) and forced vital capacity (FVC) in the lungs of 1,616 subjects (aged 35 to 79 years).
Researchers observed positive correlations between lung function and lutein, zeaxanthin, and vitamins C and E; however, the association was strongest between lutein and zeaxanthin. High carotenoid intake appeared to reduce the signs of lung aging by about one to two years. Researchers concluded that carotenoids, vitamin C and vitamin E may play a role in respiratory health.
These findings support previous research, also led by Schunemann. The earlier study, published in the American Journal of Respiratory and Critical Care Medicine (163, 5:1246-55, 2001) (ajrccm.atsjournals.org), indicated that antioxidant vitamins play a role in respiratory health, although vitamin E and beta-cryptoxanthin are stronger than other antioxidants.
The newer research was conducted to determine if carotenoids such as lutein and zeaxanthin are as effective in protecting lung function as other antioxidant vitamins. “Other antioxidants are also important, but may not be as important [as lutein/zeaxanthin],” Schunemann said. “They have different mechanisms of action and levels of activity.” Schunemann also commented that these findings are still preliminary and need to be studied using randomized trials.
According to Schunemann, lutein and zeaxanthin are being studied more often because little is known about them in comparison to beta-carotene, another carotenoid.
However, the importance of lutein and zeaxanthin is becoming more apparent with recent research, and increasing consumption of these nutrients can purportedly enhance lung function. “Increasing the intake of fruits and vegetables would certainly be recommended,” Schunemann said. “Whether these should be only carotenoid-rich foods is uncertain–although we have provided some evidence.”