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    Ha! Laughter really is the best medicine

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Ha! Laughter really is the best medicine

Scott Weems, author of "Ha! The Science of When we Laugh and Why," speaks with CNN's Dr. Sanjay Gupta.

Ha! Laughter really is the best medicine

Scott Weems, author of "Ha! The Science of When we Laugh and Why," speaks with CNN's Dr. Sanjay Gupta.