Over the years, scientists have held onto the promise—and socialites, the hope—that one day the holy grail of prescription drugs would exist: a fat pill—the pill that would either prevent consumers from absorbing too much fat or prevent consumers from storing fat and gaining weight. Alas, that pill has never been developed and likely never will. Researchers at the Rutgers University Center for Lipid Research know why. “Everyone is always worried about obesity,” says George Carman, director of th…