"And how well can she be eating? She needs to drop a few," Ablow said during Tuesday's episode of "Outnumbered."
The comment drew a collective cringe from the same four female panelists who had called the first lady "annoying" for her health initiatives only seconds earlier.
Despite the ridicule from his fellow panelists, the show's "one lucky guy" dug in.
"Well, no, let's be honest. There's no french fries happening? That's all kale and carrots? I don't buy it," Ablow said, adding that he would welcome nutrition advice from President Obama.
Ablow did not respond to TPM's request for comment.
Rep. Jim Sensenbrenner (R-WI) tried to make the same argument in 2011. It went over about as well as Ablow's observation.
"She lectures us on eating right while she has a large posterior herself," Sensenbrenner said. The Wisconsin Republican said later that he sent a personal apology to the first lady.
With Obama taking on House Republicans over new school lunch standards, the first lady's efforts to reduce childhood obesity are once again the focus of Fox's coverage.
Fox host Neil Cavuto even tried to bait a Super Bowl champion into criticizing Obama on Monday, but Seattle Seahawks quarterback Russell Wilson made it clear that he wasn't interested.