I hear the "snake oil" comment frequently. I agree with the spirit of the comments generally. However, the term actually refers to a bonified treatment for inflamation made from actual snakes. Americans began to bottle all sorts of knock-offs and make snake-oil claims that were false. These knock-off products which were not snake oil destroyed the snake oil repution.
http://hdlighthouse.org/see/immune/snakeoil.htm
http://en.wikipedia.org/wiki/Snake_oil
http://www.innvista.com/HEALTH/nutrition/fats/omega.htm