Demi Moore, Ashton Kutcher, Russell Simmons, and Christy Turlington Burns, among others, gathered at the Stephan Weiss Studio on Tuesday night to celebrate Donna Karan’s Urban Zen Initiative, a wellness program the designer founded to encourage integrative patient care. “I’m here pretending to be a health nut,” said Andrew Saffir. “But I don’t feel so bad since I’m sure I can smell some yogis smoking.” While a few guests enjoyed surreptitious ciggies in the garden, others reflected on their own yoga practice. “Let’s just put it this way, I try to do yoga everyday,” said Karan, who admitted to missing her morning session because she was preparing for the ten-day forum currently being held at the studio. Amy Sacco isn't quite so disciplined. “I get into difficult positions all the time,” said the nightlife impresaria. “But it usually has to do with my big mouth and not my abilities as a contortionist.”