Table 1.

The NOVA classification, from Monteiro et al. [20] and Steele et al. [24]

NOVA group	Purpose	Types of processing and examples
Minimally processed foods	To preserve foods and make it possible to store them and, sometimes, also to reduce the stages of food preparation (cleaning and removing inedible parts), to facilitate their digestion, or to render them more palatable (grinding or fermentation).	Unprocessed foods altered by industrial processes such as removal of inedible or unwanted parts, drying, crushing, grinding, fractioning, roasting, boiling, pasteurisation, refrigeration, freezing, placing in containers, vacuum packaging, non-alcoholic fermentation and other methods that do not add salt, sugar, oils or fats or other food substances to the original food. The purpose of these processes are to preserve foods, make them suitable for storage, safe to eat, edible to eat or more pleasant to eat [24]. Minimally processed foods include fresh, frozen or dried fruits and vegetables; grains; legumes; meat, poultry, fish; eggs; milk; fruit or vegetable juices (with no added sugar, sweeteners or flavours); flakes or flour made from corn, wheat, oats; seeds (with no added salt or sugar); herbs and spices, plain yoghurts; tea, coffee and water.
Processed culinary ingredients	To obtain ingredients used in the home and in restaurant kitchens to prepare, season and cook unprocessed or minimally processed foods, to create varied and enjoyable dishes.	Substances obtained directly from minimally processed foods or from nature by industrial processes such as pressing, centrifuging, refining, extracting or mining. Examples include vegetable oils; butter and lard; sugar and molasses; honey and starches from corn and other plants and salt.
Processed foods	To prolong the durability of minimally processed foods and make them more enjoyable, by modifying or enhancing sensory qualities.	Products made by adding salt, oil, sugar or other processed culinary ingredients to minimally processed foods, using preservation methods such as canning and bottling or for breads and cheeses, non-alcoholic fermentation. Examples include canned or bottled vegetables and pulses in brine; salted nuts and seeds; salted, dried, cured or smoked meats or fish; canned fish; fruit in syrup and freshly made unpackaged or artisanal breads and cheeses.
Ultra-processed foods	To make long-lasting, readily available and accessible (ready to eat) hyperpalatable and highly profitable (using low-cost ingredients) branded products, often consumed as fast food, snacks or desserts [24], to displace all other food and drink groups [20].	Formulations of ingredients mostly of exclusive industrial use, which result from a series of industrial processes. Many processes require sophisticated equipment and technology. Processes include fractioning whole foods into substances, chemical modifications of substances, assembly of unmodified and modified food substances using industrial techniques such as hydrogenation, hydrolysation, extrusion, moulding and pre-frying, frequent application of additives whose function is to make the final product palatable or hyper-palatable (‘cosmetic additives’) and sophisticated packaging, usually with synthetic materials [20].
		Ingredients often include sugar, oils and fats and salt, which are usually used in combination and substances that are sources of energy and nutrients but of no or rare culinary use. These include high-fructose corn syrup, hydrogenated or interesterified oils and protein isolates; cosmetic additives such as flavours, flavour enhancers, colours, emulsifiers, sweeteners, thickeners, and anti-foaming, bulking, carbonating, foaming, gelling and glazing agents and additives that prolong shelf-life, protect the original properties of the product or prevent microorganism proliferation.
		Examples include soft drinks; sweet/savoury packaged snacks; chocolate; ice cream; mass-produced packaged breads; margarines; biscuits, pastries and cakes; breakfast ‘cereals’, ‘cereal’ and ‘energy’ bars; ‘energy’ drinks; milk drinks, ‘fruit’ yoghurts and ‘fruit’ drinks; ‘cocoa’ drinks; ‘instant’ sauces; infant formulas and follow-on milks; ‘health’ and ‘slimming’ products such as meal replacement shakes and powders. Ultra-processed foods also include many ready-to-heat products including pre-prepared pies, pasta and pizza meals; chicken and fish ‘nuggets’ and ‘sticks’, sausages, burgers, hot dogs and other reconstituted meat products and powdered and packaged ‘instant’ soups, noodles and desserts.