Just how much does your mind determine your body? In the NPR article, Hotel Maids Challenge the Placebo Effect, Maids start losing weight, once they change their mindset. They don't change their daily routine. They simply change perspective.
I like this article because of the new distinction in the placebo effect. In the past, the placebo effect is usually considered effective for subjective experience, such as feeling less pain, or feeling less depressed. In this case, it's about changing physiology, by changing your mind.
This article also reminds me of a friend who suddenly dropped a lot of weight. He said he couldn't lose the weight, no matter how much he worked out, until he one day saw himself thinner. Once he made up his mind, his body followed.
As Napoleon Hill would put it, "What the mind of man can conceive and believe, it can achieve."