Helen Mirren opens up about her insecurities, being asked to be the face of a major beauty campaign at 69

Even Helen Mirren has moments of self-doubt.

The 71-year-old actress spoke at the Cannes Lions Festival on Tuesday about launching the "All Worth It" initiative to give confidence training to young people in the U.K., and talked about her own insecurities.

"It's a worm in the brain. I don't think any of us are ever absolutely free of it," the Oscar-winning actress said. "But it is particularly debilitating and useless in the young."

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"Well, I'm a good actress, you know," she continued about how she deals with it. "That is what it is all about, you just act your way through it. You are not the only one who is going to suffer great self-doubt and insecurity."

Mirren also reflected on diversity, and being asked to be a L'Oreal beauty ambassador in 2014, when she was 69 years old.

"It was about bloody time!" Mirren said of the choice. "I thought, at last there has been a shift [in the fashion industry] -- I'm talking about age and beauty, but also diversity."

The actress recalled living with fashion photographer James Wedge in the '70s, when "he could not get a black girl on the front of a magazine."

"Now, finally, the breakthrough has happened. ... And now it's great to see older women, different genders, different religions -- the whole diversity of the world we are living in," she said.

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Of course, everyone can agree that Mirren's still got it. Last November, James Marsden admitted that he's had a "massive crush" on the legendary actress for years during his appearance on The Ellen DeGeneres Show, and was overwhelmed when Mirren ended up surprising him on-air.

Watch the cute moment above.