Researchers from Vanderbilt University, Nashville, TN, recruited 90 respondents to measure and test how laughter can burn up calories. The respondents were not informed that the real reason was to calculate their laughter because the researchers wanted genuine laughter to come out from the respondents. They were asked to watch five different comedy clips and were told that they were being tested for their emotional reaction to different shows. Result: those laughing burned 20 per cent more kilojoules. Laughing 10-15 minutes a day would burn 2.2 kilograms a year the researchers reported.

Read the research abstract at http://cat.inist.fr/?aModele=afficheN&cpsidt=18495666