The Canadian Food Guide recommends limiting the consumption of highly processed foods. What is a processed food? Are all processed foods the same? Is there a difference between one processed food and another? Since 2009, there has been a tool, little known to the general public, that allows foods to be categorized according to their degree of processing: the NOVA classification.

NOVA classification

The NOVA classification was developed by researchers affiliated with the Center for Epidemiological Research in Nutrition and Health at the University of São Paulo in Brazil. It allows foods to be classified according to the degree, nature, and purpose of their processing rather than by their botanical or animal origin as with traditional food groups (vegetables and fruits, cereal products, milk and substitutes, meats and substitutes). The NOVA classification is divided into four categories.

The four categories of the NOVA classification

In their report, "The United Nations Decade of Nutrition, the NOVA Food Classification, and the Problem of Ultra-Processing," the researchers behind the classification define the nature of foods belonging to the four categories.

Category 1 of the NOVA classification

The first category includes unprocessed or minimally processed foods. Unprocessed foods include the edible parts of plants (seeds, roots, stems, leaves, fruits) and animals (eggs, milk, muscles, offal), mushrooms, algae, and water. As for minimally processed foods, these are unprocessed foods modified by processes such as roasting, non-alcoholic fermentation, and grinding. These processes aim to optimize food preservation or make them edible. Examples of foods in this first category are:

• Fresh fruits and vegetables, pressed, refrigerated, frozen, or dried
• Mushrooms, fresh or dried
• Fresh or pasteurized fruit or vegetable juices, without sugars, sweeteners, or flavorings
• Cereal products such as rice, millet, or barley
• Porridges, flakes or flours
• Pasta, couscous, and polenta, made from flours, flakes or grits, and water
• Nuts and seeds, with no added salt or sugars
• Legumes such as white beans, green lentils, and chickpeas
• Meats, poultry, fish, and seafood, whole or cut, refrigerated or frozen
• Eggs
• Milk, pasteurized or powdered
• Plain yogurt, with no added sugars or artificial sweeteners
• Aromatic herbs and spices such as pepper, cinnamon, thyme, and oregano, fresh or dried
• The tea, coffee and drinking water

Category 2 of the NOVA classification

The second category includes processed culinary ingredients. These are substances derived from foods in the first category through processes such as refining, drying, and pressing. These processes aim to create durable products used to season or cook foods from the first category. Indeed, they are generally not consumed alone but in combination with foods from the first category. Processed culinary ingredients include:

• The salt
• Sugar, molasses, honey, and maple syrup
• Butter, lard, bacon, and vegetable oils such as olive oil and sesame oil
• Starches (e.g., corn starch)

Category 3 of the NOVA classification

The third category corresponds to processed foods. These foods are obtained by adding ingredients from the second category (salt, sugar, oil, etc.) to foods from the first category. The processes involved in their production include various cooking and preservation methods (e.g., non-alcoholic fermentation). The purpose of these processes is to improve the durability or organoleptic qualities of the foods from the first category. Processed foods generally consist of a few ingredients and can be recognized as modified versions of foods from the first category. They can be consumed alone or with other foods. Examples of processed foods include:

• Canned fish
• Fruits and canned vegetables
• Nuts and seeds, sweet or savory
• Dried, salted, or smoked meats
• Fresh cheeses
• Fresh bread

Category 4 of the NOVA classification

Finally, the last category includes ultra-processed foods. These are products made mainly or entirely from substances derived from foods and additives, with little or no intact foods from the first category. Their ingredients generally include sugars, salt, and/or fats (e.g., oils). Regarding the additives used in their production, one can find dyes, colorants, preservatives, stabilizers, emulsifiers, and flavorings. These additives serve to enhance the organoleptic qualities of the foods or the final appearance of the product. Several food processing methods are used in the manufacture of these foods, hence the term "ultra-processed." These methods include, among others, hydrogenation, hydrolysis, and extrusion. The goal of these processes is to produce convenient, appealing, and cost-effective products. In this fourth category, we find:

• Carbonated, energy, dairy, or fruit drinks
• Sweetened yogurts
• The snacks packed, sweet or savory
• Ice creams, chocolates, and candies
• Industrial breads and bakery products
• Margarines and spreads
• Cookies, pastries, cakes, and cake mixes
• Breakfast cereals, cereal bars, and energy bars
• Ready-to-use sauces
• Infant formulas
• Meat extract-based products such as chicken kibbles and sausages
• "Health" and "slimming" products
• Ready-to-heat products

The usefulness of the NOVA classification

In recent years, the food supply has evolved significantly. With the emergence of ultra-processed foods, the usual food groups (vegetables and fruits, cereal products, milk and substitutes, meats and substitutes) no longer allow them to be distinguished from other foods. Moreover, research using the NOVA classification observes that ultra-processed foods have negative impacts on diet. On the one hand, they promote increased consumption of foods with high energy density, saturated fats, trans fats, and free sugars (added sugars and those naturally present in syrups, honey, and fruit juices). On the other hand, they decrease the intake of fiber and micronutrients such as iron, zinc, and vitamin A. Some studies also observe a direct association between ultra-processed foods and hypertension, obesity, metabolic syndrome (a set of factors increasing the risk of developing type 2 diabetes, suffering from heart disease, and having a stroke), and dyslipidemias (blood profiles where lipid levels are abnormal). With the NOVA classification, consumers can differentiate foods into four categories and make informed dietary choices.

In conclusion

A healthy diet should favor foods belonging to the first category, that is, unprocessed or minimally processed foods. As for processed foods, they should be limited, and ultra-processed foods avoided. The best way to achieve this: cook more!

References 

• Monteiro, Carlos Augusto, et al. “NOVA. The star shines bright.” World Nutrition, vol. 7, no. 1-3, 2016, pp. 28-38.
• Monteiro, Carlos Augusto, et al. “The UN Decade of Nutrition, the NOVA Food Classification and the Trouble with Ultra-Processing.” Public Health Nutrition, vol. 21, no. 1, 2017, pp. 5–17., doi:10.1017/s1368980017000234.
• https://guide-alimentaire.canada.ca/en/healthy-eating-recommendations/limit-consumption-highly-processed-foods/

Article written by:

Marie-Noël Marsan, Nutritionist