The twin appear in a promotion for McDonald's Happy Meals, where children can get a free Mary-Kate and Ashley photo album, handbag or box of crayons.
The campaign broke on September 8, with images of the twins appearing in stores and on the McDonald's France . There is also a television campaign to promote the Happy Meal.
However, it seems that the Olsen twins are less than inspirational figures to get children to eat cheeseburgers after this summer's revelation that Mary-Kate was being treated for an eating disorder. She was discharged from a clinic in July, with her publicist strenuously denying rumours that Mary-Kate's treatment was related to drug use.
The news comes hot on the heels of revelations that heiress Paris Hilton, whose slim figure suggests that she is not a regular at the burger bar, had been considered for a Burger King ad campaign.
It also follows an embarrassing few months for McDonald's globally, as the fast-food firm fights the success of the documentary 'Super Size Me', covering the exploits of Morgan Spurlock after he decides to eat only McDonald's food for 30 days.
Mary-Kate and Ashley have been stars since they first appeared as babies on the US sitcom 'Full House'. They have earned hundreds of millions of dollars and, up until this year's dramas, were seen as ideal spokespeople for brands because of their squeaky-clean image.
They have lent their names to a vast number of products including a clothing range, housewares, fragrances and a vast number of DVD titles. This summer they had their first theatrical release with 'New York Minute'.
Only weeks before revealing that she was being treated for an eating disorder, Mary-Kate had sent up criticism that she was too skinny in a sketch on the US TV show 'Saturday Night Live'.
The twins played members of the paparazzi and shouted at actors pretending to play them "Mary-Kate, you're so skinny, eat a sandwich" and "I hear they get paid in cocaine".
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