Watching TV sitcoms may help health because there is a direct correlation between laughter and positive effects on the body and mind, a U.S. researcher says. Dr. Lee Berk, a preventive care specialist and psychoneuroimmunologist, said watching sitcoms can contribute to improved overall health because people who laugh often are more likely to exercise vigorously and eat healthier. A study, \"The Power of Laughter,\" determined that sense of humor is the top quality that people find attractive in a person, over other traits like physical appearance and intelligence, while more than 70 percent of people agree that laughter, as a personality trait, can open doors and create opportunities in the workplace, the study found. Ninety-two percent of those in the study agreed everyone needs laughter, with humor about everyday life ranking as the No. 1 type of humor. The study was conducted in October in a national survey of 1,200 people ages 21-59 plus some viewers of cable\'s TV Land. \"Our study validates that watching sitcoms is the No. 1 way people seek out and found laughter,\" Berk said. \"That is very significant since this is an accessible way, be it alone or with others, that Americans can obtain the psychological and physical benefits of laughter such as feeling less stressed and depressed, having more optimism and vigor, along with lowering blood pressure, stress hormones and enhancing components of immunity.\" TV Land viewers said \"Hot in Cleveland\'s\" Betty White made them laugh the most, the study found.