Well, I've now found out that meridians are related to acupuncture - I didn't know that; I had thought it was some Tai Chi thing.
I think that acupuncture is in the dubious, but not 100%, bullcrap group. There seems to be some substantiation that some of it works some of the time. I'm not clear that it isn't placebo when it works. (BTW, I have no interest in yyreg's thread - I can read Cochrane myself and see that most of the acupuncture studies are "insufficient data" with a couple of "maybe small effect".)
There are some recent PubMed indexed studies suggesting possible mechanisms by which it might work. And they're from reputable sounding places. (This is no longer guaranteed at PubMed, they're getting some weird stuff in there now.)
A couple in 2006:
Subcutaneous tissue fibroblast cytoskeletal remodeling induced by acupuncture: Evidence for a mechanotransduction-based mechanism.
http://www.ncbi.nlm.nih.gov/entrez/...ve&db=pubmed&dopt=Abstract&list_uids=16511830
It has been determined that endomorphin-1, beta endorphin, encephalin, and serotonin levels increase in plasma and brain tissue through acupuncture application. It has been observed that the increases of endomorphin-1, beta endorphin, encephalin, serotonin, and dopamine cause analgesia, sedation, and recovery in motor functions. They also have immunomodulator effects on the immune system and lipolithic effects on metabolism.
http://www.ncbi.nlm.nih.gov/entrez/...ve&db=pubmed&dopt=Abstract&list_uids=16393878
Some big German study is going on.
http://www.ncbi.nlm.nih.gov/entrez/...ve&db=pubmed&dopt=Abstract&list_uids=16511742
Now my opinion on Chinese medicine is similar to my opinion on herbalism - it's a tradition born from a mix of folk wisdom, anecdote, trial and error, sheer guesswork and magical thinking. Some of it probably works to some extent, but when it does it's not because of the claimed underlying causes - no chi, no sympathetic magic. But hmmm, maybe not 100% woo.