Sorry to hear about your condition. As with all cancer treatment, they do vary from person to person based on their current condition. I would suggest asking your oncologist before integrating a full smoothie into his diet. The NutriBullet can help bring nutrients and hydration as you heal. However with colon cancer, some people may not tolerate much of anything after surgery. If anything, I would start off slow with something lower in fiber to see how well you tolerate it. Always check with your oncologist and a dietitian that specializes in oncology.