Three recent papers in two journals point out the power of certain foods to ward off disease. In the October issue of the American Journal of Clinical Nutrition, Lenore Arab and her colleagues at the University of North Carolina at Chapel Hill (UNC-CH), describe the results of a meta-analysis that reviewed 300 papers looking at the effects of garlic on cancers of the digestive system. In all, they found that people who regularly consumed garlic--raw or cooked--face half the risk of stomach cancer and a third the risk of colorectal cancer as people who eat little or none. The same doesn't hold for garlic supplements. Although they say that the meta-analysis by nature may overstate the benefits of garlic somewhat, the findings were consistent. And earlier work has shown that allium, a compound found in garlic, at least partially protects animals against cancers.
Steven H. Zeisel, also of UNC-CH, relays the protective effects of choline in a supplemental section of this week's issue of the Journal of the American College of Nutrition. "Research with animal models shows that if you don't have enough choline during pregnancy, the brain doesn't develop normally and the babies are born either with defective memory or lower memory capabilities that last throughout their lives," Zeisel says. So he tested the flip side of the coin, giving rats choline in utero or during the second week of life. He found that these animals indeed had better than average memories for life, functioning that is most likely improved thanks to developmental changes in the hippocampus.
Choline is readily available in eggs, which are also a rich source of lutein and zeaxanthin. Another paper in the same journal issue explains how these carotenoids may help protect the eyes from oxidative damage, thereby reducing the risks of cataracts and age-related macular degeneration. Lutein and zeaxanthin are also found in certain vegetables, such as spinach, but eggs are a particularly good source because their lipid matrix makes the carotenoids easier to absorb. "Although additional research studies on the relationship betwen egg consumption and diseases of the eye are necessary," says the paper's author, Jeffrey Blumberg of Tufts University, "these findings show promise as a key to decreasing the risk of leading eye diseases."