My relative was diagnosed with Multiple Myeloma (which is a form of bone marrow and blood cancer). She began taking two Grapefruit Seed Extract supplements a day, and drinking two green teas a day. The green teas were plain, with nothing else added to them. Her cancer regressed when she did that, and now she does not have it anymore. She had done nothing else differently aside from that, so I attribute it to that. So yes, I would say that the Grapefruit Seed Extract definitely helps, at least in her case, as well as green tea. You can by the GSE for about $9 a bottle on Amazon, and she just used plain ol' Lipton green tea bags. Hope this helps someone.