Here’s the skinny: French diet guru upgrades at Yorkville condo tower

French diet expert Jean-Michel Cohen paid $1.5 million for a two-bedroom unit at the Leighton House condominium tower, according to records filed with the city yesterday.

Cohen and his nutritionist wife, Myriam, also own a smaller unit on the same floor in the 46-story building at 360 East 88th Street near Second Avenue, which they put on the market in February for $1.2 million.

Cohen created the Bon Appétit diet, a weight loss plan based on changing one’s eating habits. A frequent television and radio guest in France, Cohen is the author of bestselling diet guides “Maigrir: Le Grande Mensonge” (Weight Loss: The Great Lie) and “Savoir Maigrir” (Know How to Lose Weight).

A representative for Cohen’s company did not immediately return a request for comment.

They bought the more recent apartment, Unit 24D, from Margaret Johnson, an attorney who decided to move out of state, according to her listing agent, Carter McHyman, a vice president with Prudential Douglas Elliman.

Johnson, who purchased the apartment in 2005 for $1.26 million, also previously owned another unit in the 163-unit building.

“What happens is that people love the building,” McHyman said. “Basically, people buy small apartments there, and then as things change in their life and as [their] families get bigger, they love the building so much that they don’t want to leave the building. They just buy larger apartments.”

Johnson listed the unit at $1.68 million last May. Soon after, the Cohens approached her about buying the apartment for $1.5 million, but she decided the offer was too low, McHyman said. But after some time passed, she decided to accept their offer, and luckily they were still interested, he said.

The deal closed March 16.

The southeast corner apartment is 1,338 square feet and could be converted to a three-bedroom, the listing said.

The Cohens’ other apartment in the building is Unit 24A, a 984-square-foot two-bedroom unit that they bought for $957,500 in 2010. The unit is listed with Joelle Larroche and Margaux Larroche, both of Elliman, who were not immediately available for comment.

It’s not clear whether the Cohens used a broker to buy Unit 24D.

Cohen made headlines last May when he was sued by a rival diet expert, Pierre Dukan, the creator of the protein-based Dukan Diet. Dukan accused Cohen of libel after he told a French nutrition magazine that the Dukan Diet causes health problems, according to news reports.

Leighton House, completed in 1990, was developed by General Atlantic Realty. The building has a full-time concierge, health club and private playground and garden.