Kirstie Alley's 100-Pound Weight Loss: All the Details! - OK! Magazine

The striking blonde model strutting down the runway wearing Zang Toi stole the show at NYC's Lincoln Center when the cheering crowd realized the 5-foot-7-inch beauty was Kirstie Alley, who once tipped the scales at 230 pounds — and who is now 60 years old and a proud size 4! "It was so exhilarating," she told OK! exclusively about her runway experience. "I had the best time of my life!"

Before Dancing With the Stars, it had been a rocky road for Kirstie, who'd struggled with her weight through the years. But now she tells friends she's feeling better than ever.

"Kirstie says she's a new woman," a source tells OK! in this week's issue!

OK! NEWS: KIRSTIE ALLEY REVEALS "I'VE LOST 100 POUNDS"

"When she was heavy she was too embarrassed to go out. She hated herself and basically spent her time either with her kids or alone. In her own words, she was a hermit."

But Kirstie's time on DWTS really kicked off her newest weight loss.

OK! GALLERY: KIRSTIE ALLEY ROCKS THE RUNWAY AT NYC FASHION WEEK!

FOR MORE ON KIRSTIE'S WEIGHT LOSS, PICK UP THIS WEEK'S ISSUE OF OK! — ON SALE EVERYWHERE NOW!