PepsiCo announced a makeover for its popular snack brands, Cheetos and Doritos, introducing "Simply NKD," a new line without artificial colors or flavors.The toned-down versions will be available in stores starting December 1.While the snacks will not be colorless, they will have a lighter shade similar to tortilla chips, moving away from synthetic dyes currently found in about 40% of PepsiCo's US products.