California is to become the first US state to ban restaurants from preparing food with trans fats, which clog arteries and raise the risk of heart disease.
Governor Arnold Schwarzenegger has signed off legislation committing to phasing in the bill across the state from 2010.
A number of cities, including New York City and Philadelphia, have banned trans fats but California will become the first to do it state-wide.
"Consuming trans fat is linked to coronary heart disease, and today we are taking a strong step toward creating a healthier future for California," said Schwarzenegger, in quotes carried by Reuters.
Last October, the former Hollywood star signed a bill banning artificial trans fats in food served at public schools.
A spokesman for the California Restaurant Association said its members will comply with the law, adding that many are already voluntarily moving away from the use of trans fats.
Last December, the Food Standards Agency said there is no need to ban harmful trans fats in the UK, as voluntary reductions by food companies had already significantly reduced consumers' exposure.
By Daniel Thomas
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