"Gratitude is the healthiest of all human emotions. The more you express gratitude for what you have the more likely you will have even more to express gratitude for." -- Zig Ziglar

It's nice to be thankful--but did you know how physically powerful it is to express gratitude, too?

According to Portland State University researchers (psychology professor Cynthia Mohr, business professor David Cadiz, and Alicia Starkey, a recent Ph.D graduate in psychology), together with Clemson State University professor Robert Sinclair, expressing workplace gratitude has a positive effect on physical and mental health.

More specifically, the study shows that being thanked more often at work leads to better sleep, healthier eating and fewer headaches, because this gratitude improves work satisfaction.

Researchers studied a group of nurses, who, as Cadiz explains, "tend to have a thankless job." It's a profession that is "very physical, and they're often being screamed at by patients who are at their lowest. When nurses receive gratitude, it boosts them."

Cadiz also said that nurses align their identity very strongly with their profession. In fact, they even look out often for patients more than they do themselves. When these nurses were thanked at work, this gratitude positively matched with their identity, which gave them job satisfaction and increased their self-care.

Consider applying this research to your own life in order to keep yourself healthy as you navigate the workforce.

Include gratitude in a business plan and create formal or informal opportunities for gratitude to be expressed in your business or organization.

Adds Cadiz, an employee who receives positive feedback is healthier, which ultimately impacts your bottom line:

Preventing headaches and other stress-related symptoms means fewer sick days, and, in this case, cuts down the cost of replacement nurses and overtime pay.

Thanking a colleague improves both their health and yours. If you want to make a significantly positive impact on the quality of your life (and increase the likelihood of job retention at the same time), then express gratitude. You'll find fewer stress-related illnesses and diseases appearing in your life, and you'll even discover a healthier and happier workplace.