SAN FRANCISCO -- No stranger to the restaurant business himself, Mayor Gavin Newsom said a threat by the city's restaurant owners to shut down for a day to highlight the high cost of doing business in the city would not work.

Members of the Golden Gate Restaurant Association have threatened the shutdown to protest several recent city regulations its members have said are cutting into already meager profits.

San Francisco voters approved a measure last November requiring all businesses to provide paid sick leave to workers. And the city's minimum wage is one of the highest in the country.

Restaurant owners have also filed a legal challenge to a plan set to take effect in January that would require businesses to help provide health care for San Francisco's uninsured.

Newsom, who sold his stake in restaurants within the city before he took office but still owns inns in Napa and Lake Tahoe, said he could sympathize, but that closing down for the day would only hurt the restaurants.

"It's against their best interest," Newsom said. "These restaurants are predominantly mom and pop restaurants and small businesses. ... I would argue that the vast majority of establishments cannot afford to shut down even for an afternoon, let alone a day."

Information from: San Francisco Chronicle, http://www.sfgate.com/chronicle