Most food journalists condemn HFSS (High Fat Sugar and/or Salt) foods and UPFs (Ultraprocessed Foods) as unhealthy. Consumers may not be able to identify which foods in the supermarket are HFSS or UPF, but they are aware that each group is unhealthy. With the added attention brought online to eating healthy, consumers probably conclude that UPF products are worse for health than HFSS foods. The confounding problem is that most UPFs are also HFSS and that many HFSS foods are also UPF products. So why don’t we condemn any food within HFSS or UPF classes. The problem is that the situation is more complicated than it appears. I pose three critical questions for discussion in this blogpost:

1. Are UPFs not high in fat, sugar, or salt as unhealthy as those that are high in fat, sugar, or salt? and
2. Are HFSS foods not classified as UPFs healthier than those that are? 
3.  Can we seek a better understanding of the dangers of UPFs by coming up with a more scientific definition of the term?

The answers to these questions depend on esoteric distinctions between “minimal whole food content” and “substances extracted from foods derived from food constituents.” They also depend on whether fat, sugar and salt are more or less healthy ingredients than food additives with scary names.

What are the dangers associated with fat, sugar, and salt?

First and foremost, added calories are the primary attribute of HFSS. Excess calories in the diet, particularly if not balanced by physical exercise, are at the heart of the lifestyle paradigm of weight gain and development of chronic disease. Overeating leads to obesity which in turn leads to development of diseases such as diabetes, heart disease, cancers, and other diseases of civilization. Thus, in this paradigm, strict low-calorie diets and more physical exercise become the best treatment for obesity and associated diseases. The lifestyle perspective has been with us in some form for at least seventy years.

A new paradigm is emerging in the Twenty-First Century to explain the growing incidence of obesity and related chronic diseases. Kyle, Dhurandhar, and Allison [1] proposed that obesity is a metabolic disorder and should be treated as a disease and NOT as a personal failure to be stigmatized. In this alternate paradigm genetics, biology, our living environment, job stress, food noise, and weight stigma are among the many factors that can lead to overconsumption of calories and the onset of obesity and other chronic diseases. Obesity, when considered as a metabolic disorder, caloric control and weight loss become formidable targets for treatment. Treating the metabolic disorder of obesity rather than the externalities of the disease such as weight loss appears to be a more promising approach. Such an approach is greatly enhanced by the emergence of GLP-1 medications for obesity treatments [2].

When it comes to chronic diseases excess consumption of dietary fat is linked to some types of cancer, coronary heart disease, as well as obesity. Consumption of a high saturated fat diet is of particular concern. Replacement of saturated fats with polyunsaturated fats is recommended. Too much sugar is directly tied to weight gain, but whether it is the main factor in the growing obesity prevalence in the USA  is not clear. Excess sugar in the diet can lead to excess blood sugar. Inability to lower blood sugar by insulin response is a factor in diabetes. Salt is directly linked to hypertension, or high blood pressure, but genetics plays a role. Some individuals are more tolerant of high levels of salt than others. Certain combinations of fat, sugar, and salt lead to hyperpalatable foods that can be eaten to excess [3].

Interlude

A personal perspective for what it is worth. I have worked in food processing plants as a summer intern while an undergraduate. In the summer between my Freshman and Sophomore years, I worked at a Green Giant asparagus cannery. Although my main job was in the storage warehouse adjacent to the plant, I did work as a retort operator and with the Quality Control group in the main plant. The next summer I worked as a lab tech at R.T. French Company headquarters. Although the laboratory was attached to the processing plant, I spent very little time there. My last two summers, both before and after my Senior year, I worked as Quality Control Manager in a peach juice concentration and distilled spirits processing operation at Monarch Wine Company of Georgia. In the Fall before serving in the US Navy as a Supply Officer on the USS Blakely (DE-1072), I worked in Marketing and Product Development for Kellogg’s Frozen Foods which manufactured bite-sized eggrolls and pizza rolls.

I started my  professional career as a researcher applying basic principles of food science to the handling of fresh fruits and vegetables at The University of Georgia at an Agricultural Experiment Station. Later I moved to the main campus teaching Food Science. I taught many courses including Food Chemistry and Food Processing. I have much more experience and expertise in the types and extensiveness of industrial food processing than the epidemiologists and nutritionists who coined the phrase Ultraprocessed Foods.   

It is clear to me that the main difference between plain old HFSS foods and UPF-HFSS foods is the incorporation of chemical food additives into the formulation of UPF products. Formulation is the mixing of ingredients—similar to the preparation of a home-cooked meal not composed of a single ingredient. The other difference in an Ultraprocessed Food is the breaking up of the food matrix (or the architecture of the food itself). The most prominent food matrix in a whole food is that of fruits and vegetables that provides dietary fiber and holds in the vitamins and minerals. It is not clear to me whether the primary benefit of the matrix in food from plants is the fiber in cell walls or the release of vitamins and minerals during chewing and digestion. Note that any cutting, blending, juicing, or pureeing of fruits and vegetables in the home before eating them is also breaking up the food matrix. Home-made foods, such as a loaf of bread or a cake form a distinct matrix during the baking or other home process.

What is an ultraprocessed food?

Let’s examine two recent definitions of Ultraprocessed Foods:

1. Ultra-processed foods are industrial formulations made entirely or mostly from substances extracted from foods (oils, fats, sugar, starch, and proteins), derived from food constituents (hydrogenated fats and modified starch), or synthesized in laboratories from food substrates or other organic sources (flavor enhancers, colors, and several food additives used to make the product hyper-palatable). Manufacturing techniques include extrusion, moulding and preprocessing by frying.

One of the maddening things about trying to understand the terminology of ultraprocessing is the many modifications of the term since its inception [4]. This first definition mentions only three processes but focuses almost entirely on ingredients. One of those process operations, extrusion, is what determines the shape of different types of pasta, but pasta is not normally considered an ultraprocessed product. It mentions formulations and differentiates food and substances extracted from foods. Yet a loaf of bread baked at home or in a bakery from four ingredients (flour, yeast, salt, and water) is not classified as ultraprocessed. However, a loaf baked in a bread factory from starch flour extracted from food with one or more chemical ingredients/additives is considered ultraprocessed. Note also the that oils, fats, sugar, starch, and proteins are considered culinary ingredients and classify as Group 2 in NOVA. Finally, spices are food additives (extracted primarily from plant sources) that make a product hyper-palatable but don’t qualify as additives to avoid. What is the distinction between the non-ultraprocessed loaf and the manufactured loaf but the addition of chemical additives?

2. Ultra-processed foods are formulations of ingredients, mostly of exclusive industrial use, typically created by series of industrial techniques and processes (hence ‘ultra-processed’)

This second definition leaves the term ‘ingredients’ vague—vague enough to permit white flour as an ingredient in homemade loaf of bread or a birthday cake. Thus, the conflict with culinary ingredients in NOVA Group 2 like oils fats sugar, starch, and proteins disappears.  The emphasis is on “industrial use” such that homecooked=healthy; industrial=unhealthy. The idea that these chemical ingredients are “mostly of exclusive industrial use” is also not valid as I can find most of them on amazon.com and some of them in my local, regional supermarket. Continuing beyond the definition at this website, it cautions against the use of excessive amounts of fat, sugar, and salt when cooking at home, but a homemade cake made from scratch is still not considered ultraprocessed and one made in a manufacturing plant or a supermarket bakery is an ultraprocessed product.

Are UPFs low in fat, sugar, or salt as unhealthy as those that are high in fat, sugar, or salt? Dr. Carlos Monteiro, the father of NOVA, advises us to avoid all ultraprocessed products to maintain our health. He makes no distinction between those that are HFSS and those that are not. He also makes no distinction between consuming small amounts of a single UPF and ingesting large amounts of numerous HFSS products that are not UPFs. NOVA is a rigid classification system with binary designations. If the main aspect of UPF classification is the presence of additives and not the degree of processing, it would appear that the main health dangers are the chemical additives and NOT the level of excess fat, sugar or salt present.

Are HFSS foods not classified as UPFs healthier than those that are? In a series on Wellness in the New York Times, the writers went to great length to judge UPF status on the basis of ingredients. Classification was based on the presence or absence of what I called ultra-ingredients [chemical additives that flip a food from Group2 (culinary ingredients) or Group3 (processed foods) to Group4 (ultraprocessed foods)] with no regard for levels of fat, sugar or salt. In that same NY Times series, the author demonstrated how to substitute common spices for ultra-ingredients to turn them into hyperpalatable, but not ultraprocessed foods. I thought that the argument against these food additives (also termed cosmetic additives) was that the difference they made highly processed foods too irresistible to avoid. Again, is NOVA trying to deflect blame from too much fat, salt, and sugar to the presence of ‘cosmetic’ food additives? And how do spices which are extracts of plants, not normally considered to be whole foods, escape from being labeled cosmetic additives?

Can we seek a better understanding of the dangers of UPFs by coming up with a more scientific definition of the term? I commend the effort to develop a consistent understanding of the term. It is encouraging that the process will distinguish between effects of chemical additives and those of ‘degree of processing’. How can a simple ingredient like wheat flour be considered a whole food in acceptable items like home-made bread but a ‘substance extracted from foods’ baked in a bread factory? I also worry that Big Food will rush in to replace ultra-ingredients with spices that present toxicity problems of their own.

References

[1] Kyle, T.K., Durandhar, E.J., and Allison, D.B. 2016 Regarding Obesity as a Disease: Evolving Policies and The Implications, Endrocrinol Metab Clin North Am 45(3):511-20 https://doi.org/10.1016/j.ecl.2016.04.004

[2] Friedman, J.F., 2024. The discovery and development of GLP-1 based drugs that have revolutionized the treatment of obesity. PNAS 121 (39) e2415550121 https://doi.org/10.1073/pnas.2415550121

[3] Fazzino, T.L., K. Rohde, and D.K. Sullivan, 2019. Hyper-palatable foods: Development of a quantitative definition and application to the US Food System Database. Obesity 27:17611768 https://doi.org/10.1002/oby.22639

[4] Gibney, M.J., 2019. Ultra-processed foods: Definitions and policy issues, Curr Dev Nutr 2019;3:nzy077 DOI: 10.1093/cdn/nzy077