My husband likes to squeeze onto what I’ve been taught to call my “muffin top,” the bit of “extra” flesh just above my hips. Recently, he planted a hand on it, squeezed and made a desirous grunting noise that made me think he might eat me alive. “Baby, no!” I protested, batting his hand away. “Don’t squeeze my fat.” His face softened. “But I love it. I love this juicy little oyster,” he said, referencing the tender, most delicious part of a chicken. “It’s the best.”

Funny, I thought it was the worst.

This isn’t just a case of my particular insecurities and my husband’s sexual idiosyncrasies. Studies have shown that straight women overestimate the importance of thinness in heterosexual men’s perception of female beauty. That is to say, women think men prefer ladies much thinner -- and “oyster”-less -- than...