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LOS ANGELES (AP) -- A California woman is suing Jillian Michaels, claiming the celebrity trainer is endorsing a diet supplement that contains false advertising.

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Christie Christensen on Tuesday sued Michaels, one of the stars of NBC's "Biggest Loser." She claims she bought a product emblazoned with Michaels' picture and endorsement called "Calorie Control" last month and it has failed to lessen her appetite and she hasn't lost any weight.

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Christensen is seeking class-action status for her claims, which include untrue and misleading advertising. She is also suing Calorie Control's maker, Utah-based Basic Research.

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Michaels agent did not immediately return a call seeking comment. Basic Research said the company may issue a statement later today.

The lawsuit was first reported by celebrity Web site TMZ.