It seems only common sense that happiness should be good for our physical health, but psychological research has sent mixed signals in recent years. Some studies have found it is, while others have found no effect, and some even a negative effect.

In a new article published in the Journal of Happiness Studies, Professor Ruut Veenhoven of Erasmus University offers a possible solution to this question. In reviewing 30 studies, he finds that the neutral and negative findings for the effects of happiness on health are in studies on people who were ill at the time.

In comparison, studies on people who were in good health do find a strong positive effect for happiness on health. Professor Veenhoven suggests that happiness may not have a beneficial effect on the physical health of those who are ill, but it does help prevent people falling ill in the first place.

A particularly spectacular study on nuns found that those who were happiest in early life lived 10 years longer than those who were unhappy. Another study of 660 inhabitants of Ohio found that higher levels of happiness translated, on average, into 7.5 years more life.

人们似乎普遍认为幸福有利于我们的身体健康，但心理学研究在近些年得出一个复杂的讯息。一些研究发现幸福确实有助于我们的身体健康，而其他研究却发现幸福对我们的身体健康毫无任何影响，甚至有些研究表明幸福对我们的身体健康有着消极影响。

荷兰鹿特丹大学教授鲁特‧维恩霍文在《幸福研究杂志》上发表的一篇最新文章中，为我们找到了这一问题的答案。在回顾自己30年以来的研究时，他发现，幸福对健康所具有的不确定和消极影响只是对那些处在患病时段的人的研究。

相比之下，在对那些身体健康的人的研究过程中，发现幸福对健康确实存在巨大的积极影响。维恩霍文教授提出，幸福可能对那些患病人群的身体健康没有有利的影响，但它可以首先帮助人们避免生病。

一项特别对尼姑的惊人研究发现，那些在早期生活得最幸福的尼姑通常比那些不幸福的尼姑长寿10年。另一项对660名俄亥俄州居民的研究发现，那些幸福感越高的人往往平均寿命会增加7.5年。