Information about relative risk (or percentage increase in risk, such as the 18% above) can be misleading, then, unless it's presented in the context of absolute risk. So what's the absolute risk of getting colorectal cancer?
According to the National Cancer Institute, men 60 and younger face almost a 5% chance of getting colorectal cancer in their lifetimes, and a greater than 2% chance of dying from it. For women it's about 4.5% and 1.9%.