Rabbi Yisroel Reisman gave a shiur on this topic a few weeks ago. His opinion is that almost all of these ‘alternative cures’ ‘are not only totally Assur, they are also completely fraudulent.
The gist of the issur is that Avodah Zarah means ‘serving’ – by attributing any power to ‘zarah’ – any being, creature, or spirit other than Hashem Echad.
So therefore, using any ‘method’ that involves tapping in to the hidden/secret/invisible/spiritual/virtual/imaginary power of’ [insert wacky name or concept here] is almost always going to be real Avodah Zarah. It might not even matter whether you actually believe in it or not, if the practitioner or inventor believes in it.
Mema Nafshach – if you believe that they have powers that don’t come from Hashem, it is Avodah Zarah. If you don’t believe that they have any power at all, then you are an absolute fool for going to them for a non-existent cure.
BTW – even if they somehow did have actual power to heal, it doesn’t make it muttar. Kishuf was also assur, even though it had real power. It came from Tamei sources. I am not saying that this exists today – just “even if.”