New research on vegetables and aging gives mothers another reason to say "I told you so". It found that eating vegetables appears to help keep the brain young and may slow the mental decline. 　　On measures of mental sharpness, older people who ate more than two servings of vegetables daily appeared about five years younger than those who ate few or no vegetables at the end of the six-year study. 　　The research in almost 2,000 Chicago-area men and women doesn't prove that vegetables reduce mental decline, but it adds to mounting evidence pointing in that direction. The findings also echo previous research in women only. 　　Green leafy vegetables appeared to be the most beneficial. The researchers said that may be because they contain healthy amounts of vitamin E, which is believed to help fight chemicals produced by the body that can damage cells.