Other phytochemicals Natural phenols These molecules are smaller in size than polyphenols. Examples selleck products include Resveratol which is found in the skin of grapes and red wine and has been shown to inhibit metastasis by reducing hypoxia inducible factor-1α and MMP-9 expression in colonocytes (173) as well as inhibiting Wnt signalling and

β-catenin localisation (174). Carotenoids Carotenoids are naturally occuring pigments some of which can be converted Inhibitors,research,lifescience,medical by the body into vitamin A. Examples include β-carotene which is found in carrots, red palm oil and pumkin. Lycopene is another example of pigmented phytochemical found in tomatoes, watermelons, papaya, apricots and citrus fruit. They have been found to exhibit anti-oxidant, anti-proliferative Inhibitors,research,lifescience,medical and anti-inflammatory properties (175-177). Isothiocyanates These are Sulphur-containing phytochemicals found in abundance in cabbage,

turnips, broccoli, kale, cauliflower, watercress, brussel sprouts, mustard seeds and horseradish. They have been found to possess chemopreventative activity (178-180) against colonic cancer. Overall, diets Inhibitors,research,lifescience,medical high in polyphenols and other phytochemicals such as carotenoids, isothiocyanates and natural phenols have been shown to be protective against colorectal cancer. Foods rich in these compounds includes spices such as mustard seeds and tumeric, fruits including strawberries, cherries, apples, citrus fruit, grapes, watermelons, papaya, apricot and vegetables such as onions, brocolli, carrots, red palm oil, pumkin, leafy green vegetables and tomatoes. Inhibitors,research,lifescience,medical Consumption of green tea may also be beneficial. Zinc Animal models have shown that low zinc levels may

be associated with preneoplastic lesions and colonic carcinogenesis (181). In vitro studies suggested that Zinc supplementation may positively influence tumour cell response to anticancer drugs by altering colonic cancer cell gene expression (182). In the Inhibitors,research,lifescience,medical Iowa Women’s Health Study, intake of dietary zinc was associated with a decreased risk the of both proximal and distal colon cancer (18). A more recent prospective study by Zhang et al. did not find a role for Zinc intake with colorectal cancer risk but the authors highlighted a possible inverse association between dietary zinc and rectal cancer in women (183). Therefore, no substantive evidence is available for dietary Zinc intake however the putative inverse association in women needs to be explored further. Selenium An inverse association between Selenium supplementation and the risk of colorectal cancer was observed in several studies (184-189). Selenium supplementation by way of brewer’s yeast supplementation was associated with up to 50% reduction in the incidence of colorectal cancer (188,190). Other studies contradict these findings and show no significant associations (191-192).