Laughter is good for the heart because it prolongs life while depression increases the risk of an early death, according to two new studies.

• 美国科学家的两项最新研究结果显示,笑能使人精神愉悦,同时还对心脏大有好处;相反,心情沮丧则不利于身体健康,甚至会增加早死的危险。