Like a lot of companies, Veridian Credit Union wants its employees to be healthier. In January, the Waterloo, Iowa-company rolled out a wellness program and voluntary screenings. It also gave workers a mandate - quit smoking, curb obesity, or you'll be paying higher healthcare costs in 2013. It doesn't yet know by how much, but one thing's for certain - the unhealthy will pay more. The credit union, which has more than 500 employees, is not alone. In recent years, a growing number of companies have been encouraging workers to voluntarily improve their health to control escalating insurance costs.