Four categories of foods are proposed in the NOVA food classification, which seeks to relate food processing as the primary driver of diet quality. Of these, the category "ultra-processed foods" has been widely studied in relation both to diet quality and to risk factors for noncommunicable disease. The present paper explores the definition of ultra-processed foods since its inception and clearly shows that the definition of such foods has varied considerably. Because of the difficulty of interpretation of the primary definition, the NOVA group and others have set out lists of examples of foods that fall under the category of ultra-processed foods. The present manuscript demonstrates that since the inception of the NOVA classification of foods, these examples of foods to which this category applies have varied considerably. Thus, there is little consistency either in the definition of ultra-processed foods or in examples of foods within this category. The public health nutrition advice of NOVA is that ultra-processed foods should be avoided to achieve improvements in nutrient intakes with an emphasis on fat, sugar, and salt. The present manuscript demonstrates that the published data for the United States, United Kingdom, France, Brazil, and Canada all show that across quintiles of intake of ultra-processed foods, nutritionally meaningful changes are seen for sugars and fiber but not for total fat, saturated fat, and sodium. Moreover, 2 national surveys in the United Kingdom and France fail to show any link between body mass index and consumption of ultra-processed foods. The paper concludes that constructive scholarly debate needs to be facilitated on many issues that would be affected by a policy to avoid ultra-processed foods.
Keywords: NOVA definitions of ultra-processed foods; Ultra-processed foods; food and nutrition policy; food coding; food processing.