Thinner Than Thou by Kit Reed

Kit Reed writes books that straddle the line between science fiction and straight-ahead literature. In Thinner Than Thou, Reed posits a world in which the desire for a perfect body leads to the creation of a religious cult, the "disappearing" of the elderly, and underground "strip" clubs where people go to see "jumbo jigglers".

The concept is amusing, but the book wasn't, for me.