Question: I've just turned 40, about the time they say your eyes "start to go." A friend says I should be taking lutein. Can it help my eyes?
C.K., Boulder, Colorado
Answer: Lutein is one of a group of antioxidants called carotenoids that can help maintain healthy cells and tissues in the eye. Several studies suggest a link between lutein and a decreased risk of eye disease.
In 1994, a U.S. study supported by the National Eye Institute indicated that consumption of foods rich in carotenoids--particularly green, leafy vegetables--was associated with a reduced risk of developing age-related macular degeneration (AMD). In 1999, several studies showed that people with higher intakes of lutein and zeaxanthin, another carotenoid, had a lower risk of developing cataracts. In 2001, data from a national health and nutrition survey reported that higher intakes of lutein and zeaxanthin among people ages 40-59 may be associated with a reduced risk of advanced AMD.
Because of the promising results from these studies, the NEI is now conducting a pilot study to see how well lutein is absorbed into the bloodstream in people over age 60. This is the first step in testing the antioxidant as a possible treatment for AMD.
In addition, the NEI is supporting a study that further investigates the intake of lutein and zeaxanthin with relation to its effect on the likelihood of not developing AMD or cataracts. The results of this study, titled "Carotenoids and Age-Related Eye Disease in Women's Health," will help professionals make dietary recommendations about the benefit of eating diets rich in lutein and zeaxanthin.
I have collected numerous studies over a span of more than 50 years that support the benefits of these two nutrients on eye health and protection from AMD and cataracts. In particular, lutein and zeaxanthin have been shown to increase specific pigments in the retina (the back portion of the eye).
These are the same carotenoids, along with the familiar beta-carotene, that protect plants from the harmful effects of the sun's rays. Eating a diet rich in lutein and zeaxanthin can increase the macular pigment in the retina, offering protection from sun-related macular degeneration. In effect, they serve as God's natural sunglasses.
Include a daily supplement with lutein and zeaxanthin. Also, eat lutein-rich foods, including cantaloupe, corn, grapes and blueberries, and yellow squash, spinach, kale and collard greens.
Question: I hear that peanut butter helps prevent cancer and can even protect from heart disease. But isn't peanut butter high in fat?
J.J., Indianapolis, Indiana
Answer: Peanuts and peanut butter contain significant quantities of beta- sitosterol, an ingredient found in most plants that has been shown to inhibit the growth of cancer cells and offer protection from the most common forms of cancer we see today--breast, prostate and colon.
Peanuts and peanut butter also contain the plant chemical resveratrol (found commonly in grapes). It too has been shown to be a protective factor in reducing cancer as well as heart disease.
Studies show that adding a small handful of peanuts or one tablespoon of peanut butter to the average American diet each day can lower cholesterol by up to 14 percent and reduce heart disease by up to 21 percent.
In addition, according to a report in the Journal of the American Medical Association, eating one tablespoon of peanut butter or one ounce of peanuts (or other nuts) five or more times a week is associated with a 20 percent to 30 percent reduced risk of developing Type 2 diabetes.
Although nuts and peanut butter are high in fat, it is the type that is good for us: monounsaturated fat. Peanuts, whether in their natural form or as peanut butter, are packed with vitamin E, folate, potassium, zinc, magnesium and fiber. Be sure to limit your intake to the recommended amounts because peanuts are high in calories (about 100 per tablespoon), as is peanut butter.