The idea of taking a wheatgrass shot may not be particularly appealing, but if you want to keep cancer at bay, adding some of this powerful herb to your diet can help improve your immune system and directly inhibit the development and spread of cancerous cells. You can consume wheatgrass in raw or juiced form to enjoy the many nutritional benefits, and wheatgrass is readily available in most parts of the world. In fact, cancer patients throughout the world have used wheatgrass as a supplemental therapy for many years.