Being told you aren't ready or qualified for a role because of your age, having your qualifications questioned, and being mistaken for someone junior are all examples of ageism, or discrimination based on one's age.

Typically associated with older workers, the reality may be that young women bear the brunt of age-related biases in the workplace, according to research from McKinsey & Co. and Lean In, a non-profit working to empower women co-founded by former Meta chief operating officer, Sheryl Sandberg.

"We tend to promote young men based on potential, and young women based on what they've actually accomplished," says Rachel Thomas, the co-founder and CEO of Lean In.

The goal for workplaces, Thomas says, should be to create a supportive environment where young women can thrive. Unfortunately, ageism can be an inescapable obstacle for so many of them.

If you feel like you are being discounted for your age, Thomas recommends adopting these three habits:

Ask probing questions

If someone suggests you aren't ready for a promotion or to lead a major project, Thomas says consider asking, "What makes you say that?" with the "biggest, sweetest, sweetest smile" on your face.

A simple probing question like this one, Thomas says, can force fact-based thinking and help reveal someone's biases, allowing you to gain clarity, while subtly challenging their underlying assumptions.

Because there is always the chance of pushback, Thomas says, the words you choose, and how you deliver them, are important — particularly for young women who are being assertive or challenging the status quo.

For more pointed questions, frame it from a point of curiosity: Start the question with "I really want to understand so I can do better," or "Your opinion really matters to me so I'd like to go deeper and understand," she adds.

Build a case for your accomplishments

Keep a running list of your accomplishments, skills and contributions regardless of their size, Thomas says.

This is useful not only as a reminder for yourself, but for others when the time is right, like a performance review or when you want to take on more responsibility. The data will counter any assumptions based on age or gender that may arise.

Proactively sharing these accomplishments can keep your work visible.

Thomas, a manager herself, says she finds emails with quick reminders about recent successes particularly useful. "As a manager, you do get busy and have a lot on your plate, so that reminder can be really effective."

Find and foster authentic mentorship

Developing strong relationships with mentors and sponsors, especially in senior leadership positions, is crucial for career advancement, as they can provide guidance, advocacy and access to new opportunities.

Most people in senior positions, however, tend to be men, which can complicate the process for young women, as people often gravitate toward individuals who remind them of themselves.

Rather than directly asking someone to be your sponsor, Thomas recommends building a more natural rapport and demonstrating your value over time. "The people that choose to be your sponsor and that you build deeper relationships with are more likely to actually open doors for you."

Effective mentorship and sponsorship is a "two-way street," where follow-up is key, Thomas says.

A great way to do this is to share updates with your mentor about how their guidance has made a difference in your career. Showing them that their investment in you has made a tangible impact will motivate them to continue to offer their support.

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