Befriending your colleagues can be a delicate dance: Dish enough about yourself to encourage camaraderie, but not too much that you accidentally embarrass yourself or harm your reputation.

Karen Lynch, the CEO of CVS Health, has a tip for striking the right balance: Share whatever directly helps you solve a problem or connect with someone else. If it doesn't meet either of those two criteria, leave it at home.

"There's things that you can talk about that can make a difference," Lynch, whose business owns the CVS retail chain, insurance company Aetna and a series of other brands, recently told LinkedIn's "This is Working" video series. "And there's a fine line."

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Lynch said she followed her own advice as Aetna's president, a role she held from 2015 to 2021. Early in her tenure, she ran a company-wide town hall urging managers to take mental health more seriously. In an unplanned moment, she shared something she'd never told another colleague before, she said: When she was 12, her mother committed suicide.

The experience dramatically shaped Lynch's upbringing and helped define the adult she became. She also felt ashamed, anxious and embarrassed about it, so she spent much of her career being strictly about business, she said.

But midway through the town hall, with 50,000 employees listening, Lynch realized she could help her co-workers understand why she felt so strongly about mental health. After the meeting, an employee reached out to her.

"She'd just lost her son to suicide. And she said she didn't want to tell people ... and she said, 'You made it OK. And I feel so much better now that I'm talking about it, because maybe my story can help some other mom,'" said Lynch.

How to avoid oversharing

For Lynch, the lines between office banter and oversharing start to blur when you reveal too much personal or sensitive information, she said: "You're not going to share, 'I got into a fight with my husband last night.'"

Be tactful about what you divulge in the office, practice active listening and set healthy boundaries, experts recommend. Even setting boundaries on how long you spend chatting at work can help — or keep you from hearing too much from oversharing co-workers.

"If you have a colleague who overshares and dumps their personal life on you, and you don't have time for that, say, 'I'm so sorry, I only have five minutes to chat,'" Brandon Smith, a therapist and career coach known as The Workplace Therapist, told CNBC Make It last week.

You should also be mindful not to overshare on social media websites like LinkedIn or other professional networking forums, according to Claire Wasserman, the founder of educational platform Ladies Get Paid. She recommends asking yourself, 'What is my goal?' before posting personal comments on professional websites.

"Sometimes, when I see people share things about death in their family, I'm like, 'What is the point you're trying to make?'" Wasserman told Make It in 2022. "Any type of content you share should help another person and tie back to helping in a professional context."

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