Rich in fiber, it can also help regulate intestinal peristalsis and eliminate substances harmful to the body (too much use can cause constipation). Guava is a high-C fruit that can promote the rapid recovery of gastrointestinal mucosal cells and reduce the risk of diarrhea during radiotherapy and chemotherapy. In this case, the vitamin C in guava is stored under the skin and must be carefully cleaned. If cancer patients are constipated, they should eat a small amount or eat kiwi fruits and bananas instead.