Researchers found "clear and compelling evidence" that happiness paves the way to better health and longer lifespans.
研究人员通过实验得出一个简洁但极具说服力的证据，那就是快乐有助于健康，让人更长寿。

Scientists from the University of Illinois found positive moods reduced stress-related hormones and increased immune function.
来自伊利诺伊大学的科学家发现，乐观情绪有助于减少应压激素分泌，增强免疫能力。

It also concluded that anxiety, depression, and pessimism were linked to higher rates of disease and a shorter lifespan. People who felt intense anger or lived in stressful environments were more likely to be sick more often and died earlier.
另外，研究还总结出，焦虑、沮丧和悲观情绪和疾病发生机率联系紧密，减少人们寿命。易怒人群和生活在有压力大的环境中的人们更容易生病，寿命要比一般人短一些。

"The general conclusion from each type of study is that your subjective wellbeing, that is, feeling positive about your life, not stressed out, not depressed, contributes to both longevity and better health among healthy populations," said Prof Ed Diener, who lead the study.
此项研究发起者、艾德•迪纳瑞教授表示：“各项研究得到的总论是人们的主观幸福感，即对生活持有乐观态度、没有压力感和沮丧感，让人们的寿命延长、更健康。”

"Happiness is no magic bullet, but the evidence is clear and compelling that it changes your odds of getting disease or dying young," he added.
他补充道：“快乐并非‘神丹妙药’，但是研究结果清楚有力地证明了它能让人们更健康，降低英年早逝的机率。”