Cucumbers tend to slide out the back of a sandwich when confronted with bite force, writes Pashman in Eat More Better. Courtesy of Alex Eben Meyer, Simon & Schuster hide caption

itoggle caption Courtesy of Alex Eben Meyer, Simon & Schuster

Vending machines at the University of Arkansas in Little Rock, Ark., were stocked with more healthful snacks in 2006. Danny Johnston/AP hide caption

itoggle caption Danny Johnston/AP