It’s not often you see Lupita Nyong’o — who may well win the Best Supporting Actress statuette at this weekend’s Oscars — in the same sentence as “unbeautiful.” In addition to her acclaimed role in 12 Years a Slave, she’s nabbed high-end fashion endorsement deals and has become one of the most-watched red-carpet regulars in Hollywood.

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But — as the actress told the crowd yesterday at the annual Black Women in Hollywood Luncheon organized by Essence (which is owned by the same parent company as TIME) — she didn’t always feel deserving of the attention. In accepting her award for Best Breakthrough Performance, Nyong’o took the opportunity to address her own evolving thoughts about beauty and race.

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She explained that she received a letter from a dark-skinned girl who decided not to lighten her skin after being inspired by Nyong’o. It reminded Nyong’o that she, too, used to feel that her skin kept her from being beautiful — until a celebrity changed that for her:

I remember a time when I too felt unbeautiful. I put on the TV and only saw pale skin, I got teased and taunted about my night-shaded skin… And when I was a teenager my self-hate grew worse, as you can imagine happens with adolescence. My mother reminded me often that she thought that I was beautiful but that was no conservation, she’s my mother, of course she’s supposed to think I am beautiful. And then…Alek Wek. A celebrated model, she was dark as night, she was on all of the runways and in every magazine and everyone was talking about how beautiful she was. Even Oprah called her beautiful and that made it a fact. I couldn’t believe that people were embracing a woman who looked so much like me, as beautiful. My complexion had always been an obstacle to overcome and all of a sudden Oprah was telling me it wasn’t.

You can (and should) read the acceptance speech in full over at Essence, but it’s worth noting that Nyong’o’s story about Alek Wek is a reminder of one important consequence of a lack of diversity in Hollywood and in the fashion world. Though diversity studies tend to concentrate on numbers and percentages, personal anecdotes like the one Nyong’o related remind us that it does matter to viewers that they see themselves represented in the media. After all, if it takes a celebrity to make someone like her feel pretty, imagine what it means to those who aren’t destined for style icon status.

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Write to Lily Rothman at lily.rothman@time.com.