We asked dietitians to explain what ultra-processed foods are, what the research says about them, and where they should fit in your diet. Ultra-processed foods are part of a newer classification system of foods called the NOVA scale. Under the system, foods are grouped into four main categories, per Harvard Health:Unprocessed and minimally processed foods : These foods are in their natural state or barely altered, with vitamins and nutrients still intact. Ultra-processed foods: Ultra-processed foods are processed foods that take things a step farther, adding ingredients like artificial colors and flavors, preservatives for shelf stability, and ingredients to preserve texture. Ultra-processed foods listMany foods qualify as ultra-processed.