illustration (attribution, if any possible, is at the end of the article)
Information is Beautiful took the results of 75+ studies and meta-studies and created this visualisation. The larger the text, the stronger and more promising the evidence.
One might also read « You’re missing out on your experiences. A meditation expert explains how to live in the moment » by Brigid Schulte with Sharon Salzberg, for the Washington Post: http://wapo.st/1DMwy1j