Snake Oil
Proper Chinese Snake Oil actually works and is still sold.
The US Patent Medicine system screwed it up and changed its meaning.


When somebody says "snake oil" it's supposed to indicate a fraudulent health remedy but the reality is Chinese snake oil was in fact a perfectly safe and effective remedy. Originally snake oil came from China and was known as shéyóu; it was used as a remedy for inflammatory pain especially in the joints.

When the US patent medicine industry tried to cop it by using rattlesnakes it didn't work. Chinese snake oil is made from water snakes which in turn eat fish an do son and so forth. The result is the snake bioaccumulates omega-3 fatty acids in it's flesh and that's what'd extracted to make medicine.

So really when somebody says snake oil they're reminding us how the patent medicine industry for reasons of self interest and financial greed sometimes suppresses science, at the cost of our health and will have us believing the people responsible for this are on our side.

From:
    Snake Oil Redux
    Tourists are only encouraging a dubious Vietnamese tradition.
    http://www.naturalhistorymag.com/perspectives/102171/snake-oil-redux

    "As it happens, some Chinese snake oil, made from water snakes that consume fish, is rich in a key omega-3 fatty acid, and so could have some anti-inflammatory ef­ficacy, either taken orally or applied as a liniment—that according to an analysis reported in 1989 by Rich­ard Kunin, a nutrition-oriented physician. More recently, at Japan’s National Food Research Institute, a team of scientists led by Nobuya Shirai fed oil from the black-band­ed sea krait to mice and found that it promoted swimming endurance in the mice, whereas lard or even fish oil did not."

A more technical explanation was found by Kunin in 1989:

There was nothing wrong with snake oil until the patent medicine industry ruined it by using the wrong snake, if they'd used water snakes it would have been a useful medicine instead they distorted even the meaning of the name. Snake oil should have come to mean "Big pharma screws up again".