Colorectal cancer is the second most commonly diagnosed malignancy (excluding nonmelanoma skin cancer) in the United States (1), and for decades, epidemiologists have pointed to evidence from migrant studies and in-country time trends to implicate lifestyle factors as playing a major role in disease etiology (2). Whereas diet and nutrition have long been among
the chief areas of interest for investigators trying to identify the lifestyle factors that are responsible for causing or preventing colorectal cancer (2–6), studies of nutrients, single foods, or food groups have in many cases provided inconsistent results.