Governor Arnold Schwarzenegger signed legislation making California the first US state to prohibit restaurants from preparing food with trans fats, which clog arteries and raise the risk of heart disease.
The bill will be phased in starting in 2010 across California, a trend-setting state where diet-conscious legislation has been gaining momentum in recent years.
"California is a leader in promoting health and nutrition, and I am pleased to continue that tradition by being the first state in the nation to phase out trans fats," said Schwarzenegger, a former bodybuilding champion.
Last October, Schwarzenegger signed a bill banning artificial trans fats in food served at public schools.
California Restaurant Association members will comply with the new law, said spokesman Daniel Conway. "Many of them are already voluntarily moving away from the use of trans fats," he said.
Big guns phasing out trans fats
Trans fats are used in fried foods as an alternative to other healthier oils that break down faster under high temperatures, and in baked goods to extend their shelf life.
The consumption of trans fats – often in the form of partially hydrogenated vegetable oils – increases the risk of coronary heart disease, according to health authorities.
McDonald's Corp, the world's biggest restaurant company, will have phased out the use of trans fats at its restaurants before the California bill goes into effect, said spokeswoman Danya Proud.
Burger King Holdings Inc, the second-largest burger chain, has promised to switch its US outlets to trans fat-free oils by year-end.