American actress Salma Hayek has been exposed as one of the many secret smokers who are trying to hide their habits.
Hayek, 42, was spotted puffing away on American Spirits this weekend in Beverly Hills, outside Neiman Marcus, as her mother and one-year-old daughter Valentina waited.
The actress revealed to Marie Claire last year that she had gotten hooked on cigarettes while filming "Frida", and that she had quit last April.
"It's the s---iest vice you could possibly pick," the New York Daily News quoted her as saying.
"I've tried to quit before. But this time I'm done with it. I've changed," she said.
Experts were questioned as to why celebrities tried to hide their habit, and Antonia Russo, a Manhattan image consultant who specializes in advising performing artists, said that it was to do with being a role model.
"It's so taboo," Russo said.
"There's definitely a concept of 'people who smoke just don't care about themselves' or they're socially irresponsible.
"As a role model, you wouldn't want to be a part of that," she added.