 How many years of life are lost to potentially preventable cancers? Every year more than 5 million expected years of life are lost to lung cancer, breast cancer, and colorectal cancer alone. Therefore, identifying and proving strategies for prevention of cancer remains a priority, especially since not more than 2% of all human cancers are attributable to purely genetic factors. The rest involve external factors such as our diet. The most comprehensive summary of evidence on diet and cancer ever compiled recommends we should eat mostly foods of plant origin to help prevent cancer. This means centering one's diet around plant foods, not just whole grains and beans every day, but every meal. And when it comes to foods that may increase cancer risk, they were similarly bold, unlike many other dietary guidelines that just wimp out and just advise people to moderate their intake of bad foods, like eat less candy. The cancer guidelines didn't mince words when it came to the worst of the worst. For example, don't just minimize soda intake, avoid it. Don't just cut back on baking ham, hot dog, sausage, and lunch meats, but avoid processed meats, period, because they do not show any level of intake that can confidently be shown not to be associated with risk. Processed meat can not only be thought of as a powerful multi-organ carcinogen, but may increase the risk of heart disease and diabetes. Red meat was bad, but processed meat was worse, and that included white meat like chicken, turkey slices. So with more heart disease, cancer, and diabetes, there's no surprise processed meat consumption has been associated with increased risk of death. In Europe, they calculated that reduction of processed meat consumption to less than a quarter of a hot dog's worth a day would prevent more than 3% of all deaths. This was the second largest prospective study ever done on diet and cancer, studying more than 400,000 people. The largest ever, though, 600,000, was done here in the US, the AARP study. They found the preventable fraction to be even higher, suggesting, for example, that 20% of heart disease deaths among women could be averted if the highest consumers cut down to like a less than a half strip of bacon's worth a day.