The recommendation, Gapstur tells The Salt, is based on research. For instance, a systematic literature review on colorectal cancer published in 2011 by the World Cancer Research Fund found a statistically significant, 16 percent increased risk of colorectal cancer associated with each ounces of red and processed meat consumed per day. As the ACS points out, this is an amount of meat roughly equivalent in size to a deck of cards. In its new evaluation, the IARC offered a different risk assessment: It concluded that eating about ounces of processed meat daily will increase the risk of colorectal cancer by about 18 percent. We should note, we're talking relative risk here, and the chances of developing colorectal cancer are fairly low to begin with.