常说“感谢”有助身心健康

　　“Giving thanks” actually expresses gratitude to another person, whether verbally, physically, or even in the form of a letter - has profound effects on us, not just mentally but physically.

　　Ungrateful people are actually cheating themselves, scientists believe.

　　The mere act of thanking people releases chemicals within the body including “reward” chemicals such as dopamine and serotonin - a neurotransmitter that makes us feel serene and happy.

　　“If thankfulness were a drug,” says Dr P Murali Doraiswamy, of Duke University, “It would be the world's best selling product. It affects every major organ system.”

　　Stress hormones such as cortisol are also reduced by the simple act of thanking someone.

　　Another study at Kent State University, Salem, measured the effect.

　　Steve Toepfer had a sample group of students write letters of gratitude to people they knew.

　　Toepfer ensured the “thanks” weren't for trivial events such as a gift, but for genuine, meaningful events.

　　One group of students didn't write letters, one did.

　　The group that wrote the letters found that their levels of life satisfaction increased - and that those who were experiencing mild depression found that their symptoms abated.

　　The key, it seems, is genuine gratitude: your body has to “know” that a positive event has occurred, and that you've responded.

　　“If you're looking to increase your well-being, take 15 minutes to write letters of gratitude to someone,” said Toepfer, who published his study in the Journal of Happiness study.