Seeing someone else in a stressed state can impact our own hormonal and nervous system responses as if we were experiencing their stress first hand. Stress is more likely to spread when you've got emotional ties to the anxious person—a romantic partner, friend, or colleague, But even if it's a stranger, you're not immune. 1. Say hi.

It doesn’t get much easier than this. “Smile and say hello to coworkers who you may not usually speak to,” Gielan says. Simply connecting with people sends a positive message to your brain that’s beneficial both immediately and in the long run: Strong social support has been shown to be the greatest predictor of long-term happiness. Plus, spreading the love is good for business: One hospital that implemented this idea (they called it the 10/5 rule—smile at people who pass within 10 feet of you, and say hello to anyone within five feet) saw improvements in…