In a sense, the answer would be no, not in the traditional medical sense of treating an illness directly. If you got a broken leg you don't treat it with massage therapy. If you have cancer of the colon, you don't treat that with massage therapy. You treat the whole person who is experiencing that disease. And you help keep the stress out of the body that is perhaps compounding that disease. You keep pain diminished, which most everybody hopefully knows that pain makes everything worse, not just the feeling sense but also the function. The body parts that are experiencing pain don't function as well as they would otherwise, so when massage can do that, it is useful to treat illness.