"You're smiling, and you should be, you worked hard for this," she tells herself. "But even now, after you reached your goal, you're still not quite sure if you belong and can't get one question out of your mind: 'Am I good enough?'"
These doubts grew, she writes, when she encountered very few kids who looked like her on campus. "Some arrived on campus in limousines. One of your classmates is a bona fide movie star, another is rumored to be a real-life princess. Meanwhile, you got dropped off by your father in the family sedan."
Obama, who has been open about her upbringing by a close-knit family in a tiny apartment, reveals in the letter that she later found out her parents opened new credit cards to help pay for her tuition. She tells her younger self that "what you'll come to realize one day is that you're only seeing what you lack and not everything that your story has given you."
On a recent stop in London to promote her bestselling memoir "Becoming," Obama revealed that despite her prestigious education, remarkable career and historic position in the White House, she still grapples with some of the same insecurities today.
"It doesn't go away, that feeling that you shouldn't take me that seriously," she told telling Nigerian author Chimamanda Ngozi Adichie during the event, according to Newsweek. "What do I know? I share that with you because we all have doubts in our abilities, about our power and what that power is."
Obama continued by saying that this feeling is especially true for women of color, who are often made to feel like they don't belong in certain spaces at a very young age. "My advice to young women," she said, "is that you have to start by getting those demons out of your head."
Most people in these elite spaces, she emphasized, are no smarter than anyone else.
"I have been at probably every powerful table that you can think of, I have worked at nonprofits, I have been at foundations, I have worked in corporations, served on corporate boards, I have been at G-summits, I have sat in at the U.N.," she said. "They are not that smart."
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Michelle Obama shares the No. 1 lesson she learned from her mom