Harvard-trained neuroscientist: Avoid these 3 types of toxic co-workers 'at all costs'

Most sources of stress are easy to identify — but it's the unexpected triggers that can harm you the most. 

At work, toxic bosses, co-workers or clients can drive your brain into a stressed-out state, hurting your productivity and eroding your confidence, says Juliette Han, a Harvard-trained neuroscientist. 

"Toxic behavior isn't limited to people who are intentionally hurtful or lashing out at you," she adds. "People who gravitate towards drama or have a bad attitude about work can be just as bad for you." 

Han, who is also a faculty member at Columbia Business School and an academic advisor at Harvard Medical School, says the key to dealing with such toxic people is to learn how to spot them early on.

Here are the three different types of toxic co-workers you should "avoid at all costs," and how to handle them, according to Han: 

We all have our insecurities — but working with someone who is constantly self-critical and paranoid about their performance can be exhausting and distracting.

The signs: "If you're surrounded by people who are constantly talking to you about their shortcomings and performance anxiety, those conversations are only going to make you paranoid about your own performance," she says. The more time you spend with someone who is constantly worried about falling short or getting fired, Han warns, the more at-risk you are for absorbing their toxic behavior.

How to handle it: It's important to remember that your co-worker's victimhood mindset has nothing to do with you, Han says. Find time to decompress after spending time with them, whether it's by taking a short walk or talking to encouraging, optimistic colleagues who counteract the difficult one.

You might be getting roped into office drama without even realizing it. 

The signs: Pot-stirrers will try to quietly instigate drama, egging you on to talk negatively about your boss or other colleagues by acting like they're coming from a place of "genuine care and concern," says Han. "For example, after a meeting, they might approach you and say, 'Hey, weren't you offended by that person's comment?'" explains Han. "They want to cause issues between you and another person, but act like they're on your side." 

How to handle it: Resist the urge to feed into their negativity, either by changing the subject or deflecting the gossip with a positive remark, says Han. "You can say, 'I appreciate your concern, but I'd prefer to focus on the positive,' she suggests. Or, a simple "That's not something I'm worried about, but thank you for looking out for me" should suffice.

Naysayers at work aren't just people who disagree with you on everything or weigh in on every plan. They might frame their doubts as an attempt to shield you from a bad situation when, in reality, it's a good opportunity.

The signs: "This person is only going to support you to a restricted limit," says Han. "They need you to stay within a short leash, and might discourage you from meeting new people in the company or going after new projects if it doesn't benefit them directly." If someone constantly dissuades you from taking on stretch assignments or learning about new roles at your company, especially without explaining their concerns, they could be a naysayer. 

How to handle it: Never take advice about an important career decision from one person — always seek out multiple perspectives. Also, consider using their negativity as motivation. As Han points out, "The desire to prove someone wrong can really light a fire under you."

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