A lot of career advice boils down to various ways to fit in with whatever group you aspire to join. That's why people tell you to "dress for the job you want, not the job you have," to network with those you admire, and to police your tone to sound more "professional," among tons of other tips along these lines. 

But at least two incredibly successful women have exactly the opposite take. Sure, being mindful of others and the norms of your industry is always a good idea. But, according to these two titans, the real secret to career advancement (especially for women) isn't fitting in. It's being more truly yourself.  

"Fitting in is overrated" 

The latest superstar to offer this take is Melinda Gates, who joined an incredible roster of women in sharing their memories and insights for National Geographic's new special issue focusing on the lives of women around the world. It's produced exclusively by women writers and photographers. 

When the magazine asked Gates for her number one piece of advice for young women, she was blunt in her recommendation. 

"Fitting in is overrated," she replied. "I spent my first few years at my first job out of college doing everything I could to make myself more like the people around me. It didn't bring out the best in me--and it didn't position me to bring out the best in others. The best advice I have to offer is: Seek out people and environments that empower you to be nothing but yourself."

While superficial changes like trading in your hoodie for a suit might make sense, Gates insists that when it comes to your fundamental character and values, letting your inner light shine beats adapting to your surroundings every time. She's far from alone in thinking that. 

Pretending to be someone you're not is exhausting

No less than TV superstar Oprah Winfrey backs her up. As the talk show mogul explained in a recent Hollywood Reporter interview, her stint at storied news program 60 Minutes ended abruptly when she realized the show didn't line up with her true self. 

"It was not the best format for me," she explained. "I think I did seven takes on just my name because it was 'too emotional.' I go, 'Is the too much emotion in the 'Oprah' part or the 'Winfrey' part?' ... They would say, 'All right, you need to flatten out your voice, there's too much emotion in your voice.' So I was working on pulling myself down and flattening out my personality -- which, for me, is actually not such a good thing."

Oprah, who is certainly not short of other opportunities, up and quit to search for projects that lined up more closely with her personality and approach. That sort of abrupt departure probably isn't possible for most of us, but we can still put the central point made by both superachievers to work. 

Dressing to impress or meeting the right people won't get you anywhere if you're not in a career and a role that lines up with your true character and abilities. And not just for some sort of airy-fairy self-help kind of reason. Constantly policing yourself is exhausting, which eats into the energy you have for your actual work. 

As I noted when I originally covered the Oprah interview, research out of both Columbia and Deloitte shows that "covering" your true identity at work (whether that's your sexual orientation, your introverted nature, or your emotional soul) has a negative impact on your professional performance and psychological well-being. When fitting in comes at the cost of authenticity, the research is clear: it's not worth it. 

So next time you're pondering a career move, remember this advice. The only place where you'll truly shine is one where you can be yourself. In fact, you might even shine a little brighter in your current role if you let a little more of your real, authentic light out. Hey, it worked for both Oprah and Melinda Gates.