Why NOVA Doesn’t Go

Racoons, rats and pigs are opportunistic omnivores. Insects, grubs, birds, fish, plants, reptiles and carrion are all on the menu, as are humans when available. We are opportunistic omnivores too. Humans eat a huge variety of things, which is one reason for our evolutionary success. Nothing prepared us, however, for modern industrial food.

I wrote recently about the evolutionary dead-end of ultra-processed foods (UPFs) (1), and was immediately challenged by a cardiologist friend to define my terms.

Can we always recognize UPF products when we see them? As foods are altered in ways which make them more processed, do they inevitably become unhealthier? Are UPFs always unhealthier than basic produce? And, how exactly are they defined? Spoiler: No, no, no, and – it’s complicated.

We might as well start with the widely used NOVA classification scheme. It seems simple enough but the definition is fuzzy around the edges, as most attempts to classify the real world are, and it leaves more than a few question marks.

Here, then, is NOVA

Group 1. Basic produce

Anything you can rear, hunt, fish, grow or forage. These items might be minimally processed ie cleaned, dried or frozen, but they are generally recognizable. You know an apple or a frozen fish when you see one.

Group 2. Processed ingredients

Extracts used in cooking / processing. These include oils and fats, salt, sugars and syrups, flour, vinegar and other food acids (ie citric, malic), the spices, yeast, baking powder. Honey is here, even though it may not be processed at all.

Group 3. Processed foods

Items from category 1 that have been through a process such as cooking, canning, fermenting and/or adding ingredients from category 2. This fuzzy group includes wine but not whisky, basic bread but not biscuits, cheese but not cheesecake, fish but not fish fingers, yoghurt (unsweetened) but not frogurt. (The ‘but nots’ fall into group 4). You can generally see, with the naked eye, what group 3 products consist of.

This group is generally considered healthy but it includes processed, cured and smoked meats, which are linked (if consumed over long periods of time and in large amounts) to cardiovascular problems and bowel and other cancers (ie 1), probably via the nitrite / nitrosamine route. Next time you overdose on hot dogs, take a vitamin C chaser (2).

Canned or bottled fruits in sugar-laden syrup aren’t so good either.

Group 4. Ultra-processed foods / the usual suspects.

These foods have survived more complex forms of torture ranging from distillation, texturization and flavour modification to extrusion and moulding. They include:

Chips (or crisps), cakes, cookies, sweetened breakfast cereals and bars, most baked goods.

Sweetened carbonated beverages and most mass-produced confectionery, ice creams and sorbets.

Sausages including hot dogs, and other over-engineered meat products such as chicken nuggets.

Foods prepared at home are not usually designated as ultra-processed, even if they incorporate ultra-processed elements such as ready-made icing, and even if the finished item is full of fat and sugar, and contains emulsifiers, binders, stabilisers, antioxidants and flavorings (ie chocolate mousse cake) because a) they are made using domestic culinary techniques and b), food processing at home is, according to the NOVA definition, not for industry.

None of these definitions is greaseproof.

Home-use air fryers, ice cream makers, sous vide systems, high-speed blenders and acoustic freezers are blurring the boundaries between domestic and industrial kitchens, and a home-made cake is unlikely to be healthier than store-bought ones. Some domestic kitchens produce food for non-family members, as a small business. And the idea that a process is not group 4 because it is not sold as a weapon of mass production, seems to be borrowed from the legal definition of intent.

Another fuzzy area, m’lud. Let us move to firmer ground.

Visual inspection will not reveal the contents of a commercial Group 4 product. Take (and subsequently discard) a Froot Loop. It has some sort of coloring and a presumably cereal base, but the other 35 ingredients are visible only in the text box on the side of the pack.

This apparently simple four-category scheme leaves plenty of room for debate.

One could argue that unsweetened yoghurt, kefir and Lambic beer, currently in group 3, might be better placed in Group 1 if natural fermentation is categorized as minimal processing. Milk is in group 1, even though it goes through the unnatural process of flash pasteurization.

Is group 1 healthier? Not always …

The fruit juices in group 1 are not much better than the sodas in group 4. Despite a sprinkling of micro- and phytonutrients, their high glycemic index and load means that they really should be consumed only in moderation (3). Better eat whole fruit (4, 5).

Honey, lurking in Group 2, isn’t a health food either. The amino acid, antioxidant etc content of most honeys is insignificant, and from a biochemical and a metabolic perspective, honey is too close to table sugar to call. They are often combined ie in breakfast cereal so that the amounts of each appear less off-putting. Honey Smacks, which combine honey with table sugar and glucose syrup, are a metabolic smack upside the head (6).

The boundary line between groups 3 and 4 is even more problematic.

A simple Ploughman (bread, cheese and pickle) could be group 3, but adding mayonnaise would push it into group 4, if that mayonnaise was made with emulsifiers other than mustard or egg yolk.

Using mono and di-glycerides pushes mayo (and the sandwich) into group 4, even though mono- and diglycerides ae naturally occurring compounds. Polysorbates, stearoyl lactylates and carboxymethylcellulose are more obvious candidates for group 4, because they are synthetic.

Consuming large amounts of polysorbate and carboxymethylcellulose alters the microbiota in a way expected to degrade gut epithelial barrier function (7), which is not a good thing. The natural emulsifier lecithin does not have this deleterious effect (7). These findings support the general idea that natural is better for you than synthetic, and fit some aspects of NOVA.

However, the fact that this research was done after the NOVA scheme had emerged is a bit of a problem. If we follow the science, then surely the scheme should be modified to differentiate between natural and synthetic emulsifiers …

The type of bread used to construct the sandwich adds another set of variables.

If you bake your own bread using only the basic ingredients, that’s group 3. Commercial bread will almost certainly be 4, due to additives that extend shelf life. It may also contain added sugar. It you buy commercial, prepackaged bread in the USA, the amount of added sugar makes it taste more like brioche, but with the texture of boiled baby’s blanket. I find this stuff inedible, but Americans have been taught to like it (8).

If you make sauerkraut at home and stick to cabbage, salt, vinegar, lemon juice, caraway seeds, juniper berries and garlic, it is group 3. Brands of store-bought sauerkraut which use combinations of preservatives such benzoates and metabisulfites (9), or add sugar to the end product for taste and guar and xanthan gum for texture (10), fall into group 4. Und so weiter …

In the real world, when folk go shopping, few have enough patience to parse every food product on the shelf. NOVA is too unwieldy to use for field work, so a simplified version is needed.

Rule of thumb is that if the food product has a long list of ingredients (some suggest five or more, some fall for four, hard-liners insist on three), most of which are unfamiliar and which include preservatives, stabilizers, hydrogenated oils and added sugars or artificial sweeteners, then it is likely to be UPF. If you cannot see what is in the food, if it is uniform in shape and texture and has a long shelf life, these tend to confirm the diagnosis.

NOVA should not, however, be your (food) bible, because not all UPFs are bad for you. Baked beans, for example, are in group 4. They are perfectly healthy, especially the reduced sugar versions, and when applied judiciously to toast they present the excellent amino acid profile typical of legume / grain combinations. Tofu also falls into NOVA group 4, resting uneasily between Toblerone and Twix.

Notwithstanding, a diet based on UPFs will harm you because the group as a whole has a higher calory density and a lower nutrient density than does a whole food diet (11-16). The UPF diet has excessive GI and GL scores, which raise the risk of cardiovascular disease and diabetes (14). It also causes chronic inflammation (17, 18) and dysbiosis (19), which together raise the risk of most chronic degenerative disorders. These factors are driving the current crisis in global health, and particularly affect the uniquely vulnerable fetus and child (ie 20-24).

Adults may not have to be quite so scrupulous. The increased mortality associated with UPFs appears to be particularly linked to soft drinks and ultra-processed meat products (25, 26); so if you give these up you can relax, a little, on the other UPFs. Not too much, because their frequently higher calorie density and hyper-palatability (15) promote weight gain (8, 27, 28).

If you find you cannot give them up, the antidotes are described in many of my previous posts.

Regulatory and taxation systems struggle to deal with UPFs because the subject matter is so diffuse. Many public health problems would disappear, however, if those food companies who care for their customers’ wellbeing were to produce health-promoting industrial foods.

There is one such company, and that is precisely what they are working on.

UPF products with a shelf-life measured in years, that are designed to satiate and prevent over-eating, improve your mood, immunity and gut health, lower your blood sugar and lipids, alleviate chronic pain and more. They have to taste good, of course, and I can vouch that they do (29).

The next course will be served shortly.

REFERENCES:

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2. Mackerness CW, Leach SA, Thompson MH, Hill MJ. The inhibition of bacterially mediated N-nitrosation by vitamin C: relevance to the inhibition of endogenous N-nitrosation in the achlorhydric stomach. Carcinogenesis. 1989 Feb;10(2):397-9. 
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8. https://drpaulclayton.eu/blog/good-taste/
9. https://shop.lowesfoods.com/products/boars-head-sauerkraut/102335
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19. Severino A, Tohumcu E, Tamai L, Dargenio P, Porcari S, Rondinella D, Venturini I, Maida M, Gasbarrini A, Cammarota G, Ianiro G. The microbiome-driven impact of western diet in the development of noncommunicable chronic disorders. Best Pract Res Clin Gastroenterol. 2024 Sep;72:101923. 
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24. Costa CS, Rauber F, Leffa PS, Sangalli PDB, Vitolo MR. Ultra-processed food consumption and its effects on anthropometric and glucose profile: a longitudinal study during childhood. Nutr Metab Cardiovasc Dis. 2019;29(2):177–84.
25. Osté MCJ, Duan MJ, Gomes-Neto AW, Vinke PC, Carrero JJ, Avesani C, Cai Q, Dekker LH, Navis GJ, Bakker SJL, Corpeleijn E. Ultra-processed foods and risk of all-cause mortality in renal transplant recipients. Am J Clin Nutr. 2022 Jun 7;115(6):1646-1657.
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29. https://drpaulclayton.eu/uncategorised/ice-fishing/