You eat at least five servings of fruits and vegetables every day. You wash your hands before every meal. You drink plenty of water. And you get lots of fresh air and exercise. You take your health seriously and do what you can to limit your exposure to germs and illnesses. But how are you protecting your mental health?

New research shows that secondhand stress can be as contagious as the common cold. Prompting health experts to warn folks about the need to protect themselves from exposure to stress.

The study, conducted by researchers from Saint Louis University, took a closer look at how susceptible strangers were to what they dubbed 'secondhand stress.' In their experiment, the team asked some of the study participants to perform a public speaking or mental arithmetic challenge while a second group of participants watched. They measured the levels of cortisol and a stress-related salivary enzyme in both the speakers and the observers.

They found that the stress response in the witnesses was "proportional to that of their paired speakers and not influenced by gender." It's like the stress of the speakers was contagious - passed on to the observers through things like tone of voice, facial expressions, posture and even odor.

What's the big deal about a secondhand stress? A little stress is probably no big deal. But continued exposure to stress can lead to a whole host of health issues ranging from headaches to heart disease.

How can you protect yourself from this extra stress? One way is to identify the people in your life that always appear to be stressed-out. A co-worker, a family member, a Facebook friend. If possible, limit your exposure to this person. If that's not realistic, at least minimize how much of their stress gets passed on to you. Take a few deep breaths and try these tips for beating stress.

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