Research has shown antioxidant compounds in mango fruit have been found to protect against colon, breast, leukemia and prostate cancers. These compounds include quercetin, isoquercitrin, astragalin, fisetin, gallic acid and methylgallat, as well as abundant enzymes. The high levels of fiber, pectin and vitamin C also help to lower serum cholesterol levels, specifically Low-Density Lipoprotein (the bad stuff). Mangoes improve skin by helping to clear clogged pores and eliminate pimples. One cup of sliced mangoes supplies 25 percent of the needed daily value of vitamin A, which promotes good eyesight and prevents night blindness and dry eyes. The tartaric acid, malic acid, and a trace of citric acid found in the fruit help to maintain the alkali reserve of the body. Mango leaves, are also of use, helping to normalize insulin levels in the blood. Mango fruit also has a relatively low glycemic index (41-60) so moderate quantities will not spike your sugar levels. Mangos are also a great source of vitamin E. The generous amounts of vitamin C and vitamin A in mangos, plus 25 different kinds of carotenoids keep your immune system healthy and strong.