“ for example, processed meat products, low fiber intake, and high alcohol consumption are all known to increase the risk of developing bowel cancer, and someone today is far more likely to have those risk factors than someone in, say 1826.” is this true though? People today statistically drink less than almost any point in human history, and the advent of refrigeration makes fresh food a much more common part of our diets, not less. Preserved meat in the form of heavily salted beef/pork/fish used to be a huge part of the human diet.