Colon polyps. Diets high in fiber, calcium, antioxidants (as from broccoli/cabbage/ cauliflower/brussel sprouts; green leafy vegetables; brightly colored fruits and veggies) seem to lessen risk of colon cancer. A positive family history for polyps, however increases risk, as does personal history of polyps. Avoid highly processed foods and fast foods due to low nutrition, high preservatives, high fat.
Avoid processed food. Simple sugars and processed carbs should be avoided or limited. This includes any flour product. The fine grind makes absorption quick, and spikes your blood sugar which increases Insulin and promotes weight gain. Good fats such as olive oil and coconut oil are fine in sensible amounts. Eat a rainbow of organic vegetables and just enough protein. Also consume probiotic foods like kombucha.