Scientists and researchers aren’t quite sure why but placebos work.

A particular mind-set or belief about one’s body or health may lead to improvements in disease symptoms as well as changes in appetite, brain chemicals and even vision, several recent studies have found, highlighting how fundamentally the mind and body are connected.

It doesn’t seem to matter whether people know they are getting a placebo and not a “real” treatment. One study demonstrated a strong placebo effect in subjects who were told they were getting a sugar pill with no active ingredient.

Everything from from infertility and weight loss, Parkinson’s disease and depression have responded to placebo treatments.

This could change a lot bout how we treat illness and disease.