Joan Lunden Can’t Believe She’s Turning 70: ‘How the Hell Did That Happen’

Joan Lunden is turning 70 in September, and the former Good Morning America co-host can’t believe she’s about to hit the birthday milestone.

“How the hell did that happen,” she jokes in the latest issue of PEOPLE. But Lunden is taking the big 70 in stride.

Seeing — and sharing — the funny side of aging is the latest calling for the veteran journalist and mom of seven, including two sets of twins she welcomed in her 50s. With her new book Why Did I Come into This Room? (available now), Lunden hopes to “lessen the isolation” women can feel as they advance in years, whether it’s over constantly lost glasses or more unmentionable topics like hot flashes, declining sex drive and the urinary consequences of a weak pelvic floor.

  • For more from Joan Lunden, pick up this week’s issue of PEOPLE, on newsstands Friday

“I don’t care how pretty you are, how successful you are — you can leak a little when you’re in yoga class doing a power position,” she says, adding, “You reach a certain point in ‘It’s not your life where you’re more comfortable with yourself.’ Someone needed to open up this conversation.”

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Through personal stories informed by lots of research, Lunden, who was diagnosed with triple negative breast cancer in June 2014 and is now cancer-free, hopes she can help people live longer, better and healthier lives.

Plus, she notes, “there’s a silver lining of aging — letting go of mistakes and regrets, gaining this appreciation of life. Not everybody gets to continue aging, so let it be joyful.”