"Some dietary 'plant] substances have stronger anti-oxidant anti-proliferative effects than vitamin C, 'though] vitamin C is still an important 'factor.]
"We have noted that vitamin C has preventive effects on 'the ability of] hydrogen peroxide (H2O2) 'to interfere with communication between normal cells]....H2O2 'is] a tumor promoter....we noted that quercetin, a 'plant] chemical found in apples 'and onions] has stronger 'beneficial] effects than vitamin C in this system."
Source of "Vitamin C and Quercetin in Cancer Prevention"
Lee, Lee, Kang and Lee, Depts. of Food Science and Technology, Seoul Nat'l. U., Korea; and Dept. of Food Science, Cornell U., Geneva, NY 14456. Published in The Lancet, vol. 359, 2002.