How exactly does following a vegan diet cure cancer? You do believe a cancer patient can be cured if they just switch to a vegan diet, right? A carb-free meat diet has also been shown to reverse diabetes after a few months, that doesn't mean it's a sustainable diet in the long run, just as the vegan diet. You ridicule pill-popping meat-eaters, yet I'm pretty sure vegans have to supplement their daily diet with pills to make up for vitamin deficiencies.