Specific fatty acids and human colorectal cancer: an overview

Background: Evidence suggests that dietary fats are associated with risk of colorectal cancer. The effect of fats depends not only on the quantity, but also on their composition in specific fatty acids. Moreover, fats are peroxidizable, and peroxidation products as well as antioxidants play a role in the pathogenic process of colorectal cancer. Methods: The published literature was reviewed for the relationship between dietary intake or concentration of specific fatty acids in adipose tissue, erythrocytes, plasma or feces in relation to colorectal cancer. Results: Increased concentrations of short-chain fatty acids (SCFAs) and eicosanopentaenoic acid (EPA) seem to protect against colorectal cancer. Increased concentrations of medium-chain fatty acids (MCFAs) and arachidonic acid (AA) might be associated with increased risk. Long-chain saturated fatty acids (LCSFAs) seem unrelated to colorectal cancer, while the associations between monounsaturated fatty acids (MUFAs), trans fatty acids, polyunsaturated fatty acids (PUFAs) such as linoleic acid (LA), alpha-linolenic acid (ALA), docosahexaenoic acid (DHA), omega-3/omega-6 ratio and colorectal cancer are unconvincing. Conclusions: It is suggested that the substitution of food with high MCFAs and AA content by a SCFAs- and EPA-rich diet may contribute to reduced risk of colorectal cancer. (C) 2003 International Society for Preventive Oncology. Published by Elsevier Science Ltd. All rights reserved.