Watercress (Nasturtium officinale) :

Foods to Enhance the Detoxification Process University of Ulster scientists revealed that eating watercress daily can significantly reduce DNA damage to blood cells, which is considered to be an important trigger in the development of cancer. The research, published in American Journal of Clinical Nutrition, found that in addition to reducing DNA damage, a daily portion of watercress also increased the ability of those cells to resist further DNA damage caused by free radicals.