As public health nutritionists working in academia in the field of chronic disease prevention, we are interested in advice, scientific comments and criticisms about our research work or about public health actions that may result from it. This is the basis of the scientific and public health debate and we are delighted to participate in it. Working in the field of epidemiological research and having had responsibilities in the conduct of research with large cohort studies (SUVIMAX, NutriNet-Santé, PREDIMED2…) whose results have served as a basis for proposals for public health measures and policy, we welcome this scientific debate. However, the open debate must be based on a truly scientific basis and not dictated by the defense of commercial interests (this is the case for the food industry lobbies) or ideological or sectarian reasons, as can be seen on social networks, led by certain gurus or influencers motivated by the desire to be « liked » or to win more followers (who unfortunately are often attracted by an « anti- of everything » speech…).
In all the fields of public health (tobacco, alcohol, food,…) we are accustomed to attempts at destabilization by the industry who tries to cast doubt on science to block or delay public health measures. But lately, public health measures and the scientific work behind them have suffered a new type of attack linked, in particular, to the development of digital tools. Indeed, social networks enable all -experts and non-experts alike – to express themselves and give an opinion on any subject. Health and food «feed» many passionate debates where we often find peremptory opinions and judgments coming from people who don’t have much legitimacy. Even if they are not supported by science, these debates in the media or social networks have a certain interest: to allow scientists to hear the issues raised by the general public and how the general public interprets public health measures; and also hear the voice of those on the front lines and to answer questions from consumers or patients. So, the role of social networks can be very useful for scientists in charge of developing public health measures. This leads public health professionals to take into account the opinions of users and professionals to refine the actions themselves or the communication around those actions.
The Front-of-Pack (FOP) nutrition label Nutri-Score developed in France by an academic research team (Université Sorbonne Paris Nord, Paris 13 joined by INSERM and INRAe) does not escape this dynamic. First, Nutri-Score has been the subject of numerous criticisms by all food manufacturers since its appearance in an official report delivered in January 2014 to the Minister of Health. When first proposed by the scientists in France, absolutely no company supported Nutri-Score. All of them condemned Nutri-Score on the basis of pseudo-arguments suggesting that it is stigmatizing, reductionist, simplistic, false, incomplete, etc., while denying the results of scientific studies supporting its utility. Over four years, the major food industry lobbies developed all possible strategies to block, delay or discredit Nutri-Score. In March 2017, six large food multinationals (Coca-Cola, Pepsico, Nestlé, Mars, Unilever, Mondelez) joined forces (in what was called the Big6) to propose their common alternative to the Nutri-Score, namely the Evolved Nutrition Label, which was unsurprisingly advantageous for their products. But, the societal demand was clearly expressed by, among other things, the involvement of scientists, health professionals, consumer associations and NGOs supporting the interest of Nutri-Score as an important public health tool.
This societal pressure and scientific work payed off and brought down some of the major groups that, in the Big 6 or elsewhere, had strongly opposed the Nutri-Score. First, this was the case for Nestlé (in November 2019), then for Kellogg’s (in January 2020). It is a great satisfaction that these large multinationals have finally agreed to play the game of nutritional transparency and adhere to the Nutri-Score. This is good news considering the number of brands they represent and the type of products they sell, which are not always the most favorably placed on the Nutri-Score scale. On the other hand, some large multinationals, such as Coca-Cola, Ferrero, Mars, Mondelez, Unilever, Kraft, General Mills, and other companies continue to deny the scientific and public health and consumer demand (as expressed at the European level by the BEUC and the 43 national associations affiliated with it) and still refuse to adopt the Nutri-Score. Numerous articles published in scientific journals have well described the different strategies put in place by the lobbies to discredit Nutri-Score. This is why it is very surprising to hear or see some commentators especially on social networks re-write the story in their own way and affirm that Nutri-Score «plays the game» of the manufacturers because it would favor ultra-processed foods ! In fact, after several years of struggle Nestlé, Danone, and Kellogg’s ended up , accepting Nutri-Score and bending under the consumer demand and scientific evidence. We should rejoice about the victory of public health and continue to put pressure on all the other companies that still refuse to adopt Nutri-Score.
But it is true that the issue of ultra-processed foods is a real scientific issue, as is the issue of the effects of pesticides and organic foods (curiously, the latter two are much less frequently addressed by those who criticize Nutri-Score on social networks or in the media).
Moreover, the teams that developed Nutri-Score are also interested in these issues. They have worked with Prof Carlos Monteiro, the Brazilian scientist who developed the NOVA classification which classifies foods according to their degree of processing, and published several papers demonstrating the deleterious effects of ultra-processed foods on health, particularly in relation to the risk of cancers, cardiovascular diseases, obesity, etc. Similarly, about the issue of organic foods, the research team that developed Nutri-Score demonstrated a lower risk of cancer among consumers of organic foods in a large cohort of 69,000 subjects. But as we have said many times over, Nutri-Score does not include in its computation additives, degree of transformation or presence of pesticides. This choice is fully acknowledged not only for Nutri-Score but also for all other Front-of-Pack nutritional labels implemented in the world (for more details, see the article published in The Conversation : https://theconversation.com/le-nutriscore-mesure-la-qualite-nutritionnelle-des-aliments-et-cest-deja-beaucoup-99234), and is linked to the impossibility – given current scientific knowledge – of developing a single synthetic indicator capable of covering all these dimensions. Nutri-Score refers to a simple nutritional information system (which is already a lot!), which has been shown to be very useful in helping consumers to direct their choices towards foods of higher nutritional quality. But under no circumstances does Nutri-Score claim to be an information system on the global ‘health’ dimension of food covering the health and environmental dimensions in addition to the nutritional dimension.
To summarize the overall health dimensions of food through a single and reliable indicator, which would be able to predict overall health risk would be, obviously, the dream of any public health nutrition expert in the interest of consumers. But it is not by chance and certainly not by incompetence, if no international research team or public health structure in the world, or any committee of independent national or international experts, or the WHO, has been able to develop such a synthetic indicator. This can be explained by several factors:
1) First, the level of knowledge and evidence concerning the links with health differs according the food dimension being considered. The accumulation of extensive epidemiological, clinical and experimental studies provides for certain nutritional components (nutrients/foods) a documented and robust level of evidence of their impact on chronic disease risk ranging from “probable” to “convincing” in international classifications. For the other dimensions, in particular those referring to numerous additives, neoformed compounds or contaminants (pesticides, antibiotics, endocrine disruptors, etc.), their underlying levels of evidence differ greatly (especially in terms of human studies) even though some hypotheses of their impact on health have been advanced.
2) As a result of the above, it is currently impossible to weigh the relative contribution of each dimension of a food, to provide a synthetic score that would ideally be predictive of an overall health risk level. Some apps may offer it, but they have no valid or robust scientific basis. The methodological questions are numerous and still unresolved: precise measurement of the risk attributable to each of the dimensions, to each of the various components potentially involved, potential “cocktail effect,” etc. In fact, calculating a single index to characterize the overall health quality of a food, which could ultimately lead to an absolute clear conclusion is not based on sufficiently solid scientific bases and is therefore rather arbitrary.
3) Finally, with regard to additives and pesticides, where there is a sufficient body of evidence for a health risk, the answer from a public health viewpoint is not simply informing the consumer via a logo, but the actual removal of the chemical in question from the food chain to begin with. That would be in accordance with a health risk management principle.
It is therefore not possible to criticize Nutri-Score, nor the other front-of-pack nutritional labels such as the British Multiple Traffic Lights, the Australian Health Stars, the Swedish Key Hole or the Chilean Warning system, etc., under the pretext that they do not take into account food processing. That is a limitation that we must accept at this time. On the other hand, the concept of ultra-processed foods is an important issue which must be the subject of a specific communication to consumers complementary to that related to nutritional labelling which only provides information on the nutritional dimension. However, it is worth reminding that the vast majority of foods ranked as Nutri-Score D or E are ultra-processed foods.
The developers of Nutri-Score and the governmental structures in charge of its roll-out are aware that there is a limited number of foods for which Nutri-Score may pose problems related to the consistency of the message transmitted to consumers. This is particularly the case for beverages containing sweeteners, correctly classified by Nutri-Score (because they do not contain sugars, fats and salt and do not provide calories, as indicated on the back-of-pack Nutrition Facts table) yet are ultra-processed (presence of sweeteners). In that regard, there is a real question of consistency to resolve and it is legitimate to raise it. Yet this has nothing to do with the argument put forward by Nutri-Score opponents who condemn Nutri-Score based on the comparison of Nutri-Score assigned to Coca Cola Zero and that assigned to olive oil… We have often addressed this point and have explained on numerous occasions that Nutri-Score does not provide information in absolute value on the nutritional quality of foods. Nutri-Score provides information in relative terms in order to help consumers with comparisons between foods within the same family of foods, or for the same food, between different brands. And, in case of comparisons between foods belonging to different families, these have pertinence only if they represent real relevance in terms of the conditions of use or consumption (and which are often close to each other on the supermarket shelves). This last fundamental point is never addressed by those who attack Nutri-Score; they simply keep repeating this comparison between foods that have no reason to be compared: in fact, nobody hesitates between a can of soda and a bottle of olive oil to season a salad or to quench thirst… The real issue is to provide consumers the possibility to classify easily Coca Cola Zero vs other beverages (and to classify olive oil vs other added fats). This requires a clear re-discussion of the positioning of sweetened beverages.
But the recognition of an «imperfection» in Nutri-Score should not be the basis to condemn globally the whole system. Indeed, since Nutri-Score was developed and implemented, a regular update of the underlying algorithm has been planned, based on scientific data (without leaving room for lobbies who would like to distort Nutri-Score in their favor); and, of course, the issue about sweeteners will no doubt be addressed by independent scientists who will be in charge of this update at the European level in the near future…
But pending this update, it is now important to correctly position Nutri-Score within a coherent public health nutrition policy. It must benefit from educational support (information, communication and education for the general public, health professionals, social workers, educators, etc.) as regards its use, its meaning, its interest and its limitations. It is complementary to other public health measures and supplements in particular all general communication/recommendations regarding consumption of unprocessed food (raw or with a low degree of processing), local and seasonal foods and products containing as few pesticides as possible (organic foods). For example, for prepackaged foods, the recommendation is to choose those with the best possible Nutri-Score, preferably without any additives or with the shortest list of additives (as displayed in the list of ingredients), to favor raw foods and, if possible, organic food (with a certifying logo) and to reduce the share of ultra-processed foods in one’s diet.
Even if Nutri-Score has some weaknesses (some of which can be improved), it is also important to remind those who use this pretext to condemn Nutri-Score overall, that it works perfectly well for tens of thousands of different foods (probably for more than 98% of foods on the market). Yes, no FOP nutritional label can be 100% perfect. None of them can adequately and flawlessly cover all health dimensions of food. So we just need to be realistic and aware of the limitations of these public health tools. And if we are not able to develop a totally perfect nutrition label, it is not necessary to reject the one that has largely proven its usefulness. It is important to remember that Nutri-Score was established on the basis of solid scientific evidence that allowed the validation of both the algorithm underpinning its computation and its graphic format and its impact on the nutritional quality of food purchases. Some digital media users who disparage Nutri-Score do so by attacking the algorithm that supports it while denying or omitting to cite the numerous scientific works that validated it? Giving an opinion based solely on a personal vision and often without any legitimacy is not acceptable if the large amount of epidemiological work that supports its usefulness and its effectiveness are not taken into consideration.
We have to remind the public that the calculation of Nutri-Score is based on an algorithm developed in the mid-2000s by a team of Oxford scientists. It has been validated by multiple studies carried out since 2012 in collaboration with WHO, Australian and European researchers. Therefore, it is regrettable to see on digital media the violent criticisms of the Nutri-Score algorithm, that completely omit the multiple works carried out on large cohorts in France, Spain and many other European countries (with tens or even hundreds of thousands of people followed for several years). These major epidemiological studies have consistently found that the consumption of foods classified by the Nutri-Score algorithm in less favorable categories/colors was prospectively associate with an increased risk of developing cancers, cardiovascular diseases, metabolic syndrome, obesity and mortality from chronic diseases. This is a major point to integrate when discussing the effectiveness of a logo like Nutri-Score. From a scientific viewpoint, this is even the best demonstration that can be made regarding the relevance and reliability of the Nutri-Score algorithm in terms of the choice of the elements incorporated in its calculation, the allocation of points for the elements used and the thresholds selected. Curiously, these important scientific publications are never cited by those who condemn the Nutri-Score.
Moreover, we often witness, especially in some countries in southern Europe, attacks arguing that the Nutri-Score is not adapted to the context of the Mediterranean lifestyle and/or would oppose the beneficial model of the Mediterranean diet, while totally denying the work demonstrating the consistency of Nutri-Score with the Mediterranean food model. These absurd and unfounded attacks coming from certain influencers, web users or political and economic lobbies go so far as to call into question the methodology of articles/results published in international scientific journals that do not go in the direction they would like… Moreover, it is surprising that individuals who represent only themselves, who have never performed any scientific studies or have any publications, can criticize the methodology of articles published in peer-reviewed scientific journals and even contradict the conclusions of the authors of these papers…
This is what we have seen recently on social networks regarding the important work published in Clinical Nutrition by the Spanish nutrition epidemiology team in charge of the SUN cohort that showed (with a study population of more than 20,000 Spanish subjects followed for 10 years) the validity of the score underlying the Nutri-Score by its association with total mortality and in particular cancer mortality. These authors also showed that the algorithm for calculating the Nutri-Score was in perfect agreement with the nutritional recommendations of Spanish Public Health authorities (which are the same for Spain, Italy, Greece, etc.). Yet this important study is either not cited or it is criticized as to its methodology by opponents who wish to convey the absurd idea that Nutri-Score opposes the Mediterranean diet…
Finally the story of Nutri-Score is quite emblematic. After having faced unfounded criticism by the industry (including many multinational firms that remain very active in their fight) for several years the, Nutri-Score is now facing a new form of attack through social networks. These new criticisms are not intended to be constructive: they are not those that any citizen or professional can apply to help to improve Nutri-Score where it may present weaknesses. On the contrary, they are often violent (and sometimes insulting) attacks that aim to totally reject Nutri-Score, not seeking to improve it! Most often, they are not based on science but on a purely personal subjective view of the authors lacking any competence or interest (there are influencers, bloggers, general Internet users, economic or political lobbies, etc.) failing to take into account or discrediting scientific work that interferes with their reasoning or contradicts their claims.
It is important to remind to the detractors that scientific work undergoes a rigorous scientific process of independent peer-review before being accepted for publication in international scientific journals. The lack of common sense or humility of some opponents (sometimes because of their personal interests or due to the pressure groups they represent) is particularly surprising since these commentators have not carried out themselves or participated in scientific work (which often takes months or even years for research teams to complete). In general, they just read the work of others (and sometimes only the abstract of the articles) and interpret the information in a way to fit their personal vision! The role of a science communicator is very important and respectable, and bloggers who claim to have this mission do not substitute for scientists and it is not up to them to re-interpret work or support unsubstantiated theories…
Finally, what differentiates scientists from gurus (and some bloggers, influencers and lobbies) is that scientists carry out scientific studies and “believe what they see,” while gurus (& Cie) do not perform studies themselves and “see what they believe” in the scientific work of others, rewrite science as they wish to pass on their personal ideas or for their own benefit…
So thanks to all those on social networks who provide constructive criticism and useful reviews to improve Nutri-Score. Their comments are helpful. On the other hand, the absurd and unfounded criticisms dictated by reasons that have nothing to do with public health are unacceptable and useless!
Serge Hercberg1, Pilar Galan2, Nancy Babio3, Jordi Salas-Salvadó4.
1 Université Sorbonne Paris Nord. Equipe de Recherche en Epidémiologie Nutritionnelle U1153 (Institut National de la Santé et de al la Recherche Médicale / Institut National de la Recherche Agronomique/CNAM/Université Sorbonne Paris Nord), Bobigny, France. Unité de Nutrition et Santé Publique, Dép. de Santé Publique, Hôpital Avicenne, Bobigny, France.
2 Université Sorbonne Paris Nord. Equipe de Recherche en Epidémiologie Nutritionnelle U1153 (Institut National de la Santé et de al la Recherche Médicale / Institut National de la Recherche Agronomique/CNAM/Université Sorbonne Paris Nord.
3 Unidad de Nutrición Humana, Universitat Rovira i Virgili, Investigadora adscrita al IISPV, Reus, y al Centro de Investigación Biomédica en Red Fisiopatología de la Obesidad y la Nutrición (CIBEROBN), Instituto de Salud Carlos III, Madrid, España.
4 Departamento de Bioquímica y Biotecnología, Unidad de Nutrición Humana, Universitat Rovira i Virgili. Hospital of Sant Joan de Reus, IISPV, Reus. Centro de Investigación Biomédica en Red Fisiopatología de la Obesidad y la Nutrición (CIBEROBN), Instituto de Salud Carlos III, Madrid, España.