Is it my duty to set a friend straight (or am I being an asshole)?

Fifth dimensional circulatory system, my ass!

Oh, that feels goooood.

I am usually pretty respectful of people who believe differently than I do (I have friends who are liberal atheists,friends who are conservative Christians, as well as liberal Christians and conservative atheists for that matter).
…but I have a pretty low threshold for irrational stupidity and scams. I absolutely would say something to someone who was trying to spread belief in something this stupid.
Some may argue that we should just let people believe in their harmless woo.
Is it really harmless? I would argue that no, it isn’t. If you follow the link on that video, you get to the scam artist’s website where he is promoting his book and classes on this stupid crap. Of course. Of course there is a monetary gain associated with this.
Behind every stupid new agey/woo belief like this, there is someone who is making money off of tricking the gullible and stupid into believing in it.

If one of my friends posted something like this, I would try to find a polite way to point out why it isn’t true. The politeness part is key. If you confront them with an aggressive or hostile tone, they will shut down and not even hear what you’re saying. Being gentle and calm is important to getting someone to at least hear what you’re saying.

Again, I don’t know anything about the Healing methods the OP’s friend is pushing. If it’s silly but harmless, I’d definitely let it go. If it’s dangerous, but only to the friend, I’d DEFINITELY talk to that person privately and try to reason with him/her. But the third possibility is that the friend is SHARING dangerous information, and putting other people at risk. THAT may call for a public response. No, I wouldn’t make a Facebook reply saying “You’re an asshole,” but if she’s advocating something dangerous on Facebook, why WOULDN’T you reply with some facts explaining why her theories could be deadly?

At the risk of sounding like an actor, what’s your objective here?

Is it to put her down? Because that’s what you’ve accomplished, but I’m not sure why you’d want to.

Is it to make yourself feel superior?

Or is it to nudge her into questioning whether this stuff might just possibly be a load of bollix? Because if that’s what you want to achieve, ‘Hogwash’ isn’t going to do it. What might do it is something along the lines of ‘I’ve got to tell you, I’m sceptical as hell here. Can you point me to solid evidence that this works?’

Like Lavenderviolet said, if you want her to listen to you, you’ll achieve that better by being polite and calm, rather than snotty and dismissive. Plus, as it stands, your argument has nothing more solid to it than the other side does, so why should she pay attention to it?

Seriously - I know it’s actorspeak, but focusing on your objective and the best way to reach it can help to avoid all kinds of detours and (ironically) drama.

Do you really think you have a shot at changing her mind?

I’d venture probably not. Thus, confronting her isn’t really going to save her money or energy or otherwise make her life better.

If you don’t expect to do anything positive on her end, the only remaining justification to confront her is about your ego, not her well-being or your friendship.

I’d leave it be.

You might also forward a link to her like this one - science-based medicine looks at Eric Pearl and reconnective healing.