A large order of McDonald’s french fries is shown May 22, 2008. (Sam Mircovich/Reuters)

OAK BROOK, Illinois (Reuters) -
McDonald's Corp has
switched to cooking oils free of trans fats in all of its
restaurants in the United States and Canada, Chief Executive
Jim Skinner said on Thursday.

The restaurants made the switch over the past few months,
he said.

By the end of the year, McDonald's pies and other baked
goods will also be free of trans fats, Skinner told the
company's annual meeting.

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, the world's largest hamburger chain, was among
the first to say it would stop using unhealthy oils, but it has
been slow to make the change.

Wendy's, the third-largest hamburger chain, swapped to
trans fat-free cooking oil in 2006. Yum Brands Inc's KFC and
Taco Bell chains in the United States completed such a switch
last year.

Burger King Holdings Inc, the second-largest burger chain,
has promised to switch its U.S. outlets to trans fat-free oils
by year-end.

(Reporting by Brad Dorfman and Lisa Baertlein; editing by
John Wallace)