For families, eating right has become a monumental challenge. Cultural messages convince us that we no longer have time to cook, and food marketers spend billions persuading us that packaged, processed food is convenient, satisfying . . . and the key to happiness. Half of all our meals are now eaten outside the home. The result? Skyrocketing rates of heart disease and diabetes and unprecedented levels of childhood obesity. This crisis is movingly portrayed in author and activist Laurie David’s new documentary (coexecutive produced with Katie Couric), Fed Up!