A U.S. consumer group filed a suit against KFC for using artery-clogging trans fats in its fried chicken Tuesday.

The consumer group, the Center for Science in the Public Interest, claimed that a large number of menu items at KFC contain trans fats, more than most other fast-food restaurants.

Trans fats raise LDL cholesterol, which promotes heart disease, and lowers HDL cholesterol, which protects against it, according to studies.

"KFC knows this, yet it recklessly puts its customers at risk of a Kentucky Fried Coronary," the group's executive director, Michael Jacobson, said in a release.

KFC "does not properly warn, disclose or even tell consumers that they are eating food items prepared with the worst oil available," the group said in its legal complaint.

The group is asking the court to order KFC to switch to healthier oil for frying, or at least post signs warning the products "contain trans fats, which promotes heart disease."

KFC spokesperson Laurie Schalow called the suit frivolous and said it lacked merit. "We take health and safety issues very seriously," She said in a statement.

"We provide a variety of menu choices and provide nutrition information, including trans fat values, on our website and in our restaurants so consumers can make informed choices before they purchase our products."

Editor: Yan