ABSTRACT
Circumstances................................................................................... 151 7.2.7 Practical Conclusions ........................................................................ 152
Acknowledgment ................................................................................................... 153 References .............................................................................................................. 153
Esophageal, pancreatic, gastric, and colorectal cancers account for 17% of all cancers in the United States and lead to approximately 145,000 deaths/year, and globally close to 1.8 million deaths/year.1 Much effort has been exerted to understand the links between germline genetic defects and cancer but, for the above-mentioned cancers, these genetic changes alone account for only a small percentage of cancer incidence. By contrast, lifestyle factors such as dietary habits, tobacco, and alcohol use, and obesity seem to play a much larger role. Understanding which of these factors can modulate the risk of cancer is thus the subject of intense research and debate. There is little doubt that obesity and being overweight contribute substantially to the risk of colorectal cancer, and probably to the risk of esophageal and pancreatic adenocarcinoma as well. However, despite many years of epidemiological and preclinical studies, consensus has yet to be reached concerning the roles played by a number of specic components of the diet, such as certain vitamins and trace elements.
