Most people make the same communication mistake at work, says Adam Grant: They don't share an appropriate amount about their personal lives with their coworkers.

Workers tend to either reveal too much about themselves, which can damage their professional reputation — or they don't share enough, which can lead to decreased trust, says Grant, a bestselling author and organizational psychologist at The Wharton School of the University of Pennsylvania.

People who share too much tend to lack a sense of personal boundaries: They "love to blur the line between work and the rest of life," says Grant, who also holds a "chief worklife expert" consultant title at careers website Glassdoor. "Their offices are decorated with pictures of their families. They take work calls from home at all hours. They invite their colleagues over for dinner and even sometimes go on vacation with them."

But when you intertwine your work and personal lives, you'll probably struggle to find moments to recharge, Grant says. And if you feel pressure to always be outgoing at work or say "yes" when you don't want to, you can accidentally put yourself on a faster path toward burnout.

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The people who don't talk enough about themselves want a "strict border between work and the rest of life," says Grant. But if you don't ever talk about anything related to your non-work life, you might struggle to build trusting relationships with your colleagues, which you typically need to grow your career.

Fifty-three percent of U.S. professionals say they avoid making connections at work because they want to keep their work and personal lives separate, according to a January 2025 Glassdoor poll of over 800 workers. This can lead to loneliness, something 58% of U.S. adults struggle with, according to a 2021 report from insurance and health care company The Cigna Group.

How to strike the right balance

Sharing the exact right amount about your personal life at work requires some self-awareness and professional discretion, Grant says. His recommendation: Stick to relevant, work-related conversation topics and sprinkle in some light, personal levity when necessary.

"Think about the things you want to share that might actually overlap with what other people care about in your workplace," says Grant. Take advantage of team-building and group work opportunities — where you can bond with co-workers over a common goal, or things otherwise happening within your company, he adds.

If you struggle to strike a healthy balance of sharing, you might want to skip your office's more lax activities, Grant says. Work parties, happy hours and games of table tennis can bring you closer to your colleagues, but the environment can make it easier for you to accidentally overshare. 

"'Deep fun' is like, we're going to bond around rolling up our sleeves to tackle a problem we care about, or a mission that matters to us," says Grant, referencing a term coined by bestselling author Daniel Coyle. "That's where a lot of trust and connection and camaraderie happens in the workplace."

A CEO's simple trick to avoid oversharing

If you're still on the fence about what to share — and what not to — with your boss and coworkers, ex-CVS Health CEO Karen Lynch has a simple piece of advice: Share whatever directly helps you solve a problem or connect with someone else. If it doesn't meet either of those two criteria, don't bring it up.

"There's things that you can talk about that can make a difference," Lynch told LinkedIn's "This is Working" video series last year. "And there's a fine line."

Lynch said she followed her own advice at a town hall about mental health at insurance company Aetna, when she was that company's president. She shared a personal story about her mother committing suicide when Lynch was 12 years old, hoping to convey the importance of taking mental health seriously, she said.

Afterward, an employee with a similar experience reached out to her and thanked her for speaking up, she said. Sharing the deeply personal subject helped Lynch forge a bond with at least one employee, potentially helping change the way her organization approached mental health, she added.

Other personal anecdotes and banter can cross the line, she warned.

"You're not going to share, 'I got into a fight with my husband last night," Lynch said.

Correction: This story has been updated to reflect that Karen Lynch is the former CEO of CVS Health.

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