By: Karen Ambrosio, Oncology Wellness Specialist — Bell peppers are high in vitamins C and K, and are a source of beta carotene, potassium, folic acid, fiber, and flavonoids. Red bell peppers have significantly higher levels of nutrients, and they become a good source of lycopene, which may help to protect against prostate cancer as well as cancers of the bladder, cervix, and pancreas.