COVID-19, by breaking the old dichotomy between infectious and chronic disease and by creating risk groups based on age and metabolic dysregulation promoted by inadequate diet and sedentary lifestyle, transforms a highly contagious and global viral infection into a huge social and political challenge that forces us to think about nutrition differently.
Introduction
Nutritionists of the modern era, that is, those who began to experimentally relate the chemical properties of food to disease and to intervene to solve health problems caused by an unbalanced diet, only began their activities at the beginning of the 20th century.
Although he wasn't the first "nutritionist," Kazimierz Funk can be seen as the figure behind this brilliant beginning of nutritional science. Funk was a Polish scientist working in England, and in 1912, with the publication of an article entitled "Vitamins," he presented this concept for the first time. Funk studied amino acids and their "organic bases" and argued that certain diseases could be avoided by ensuring that certain chemical substances were present in our diet. Thus began the modern study of food and its relationship to disease. This would continue in the healthcare professions created in the 1920s in the United States, although initially confined to providing meals in hospitals and reporting to nursing staff. Dietary therapy consisted essentially of altering the consistency of food, and initial training was given by professors from the field of home economics. Later, everything would change with the intervention of nutritionists in the community, becoming yet another instrument for relieving social tensions in Latin America and then, with this unique blend of interdisciplinary knowledge, giving rise to the Porto School of Nutrition in the 1970s.
100 years since the onset of the chronic disease
The entire 20th century would thus be filled with great achievements in the field of nutritional sciences and, in parallel, in medical sciences. One of the greatest achievements of medicine was the progressive reduction of infectious diseases as the leading cause of death. In 1900, in the United States and most European countries, the disease pattern was relatively similar. In that year, the three main causes of death were pneumonia, tuberculosis, and diarrhea/gastroenteritis, which (along with diphtheria) caused one-third of all deaths. Of these, 40% occurred in children under 5 years of age. Much will change in just over 100 years.
In 1997, at the end of the century, heart and cancer diseases already accounted for 54.7% of all deaths in the USA, while in the same year only 4.5% of mortality was attributable to infectious diseases such as pneumonia, influenza, and human immunodeficiency virus (HIV) infection. In Portugal, we observed a very similar change in pattern, and in 2017, diseases of the circulatory system accounted for 29.4% of mortality and malignant tumors 25.0%, these two chronic diseases together being the main causes of mortality in the country. Meanwhile, some infectious and parasitic diseases accounted for only 1.8% of mortality in the country.
Scientific discoveries and public health initiatives have contributed significantly to this paradigm shift in mortality. For example, the 19th-century discovery of microorganisms responsible for infectious diseases such as cholera and tuberculosis; improvements in sanitation in many cities; the discovery of antibiotics; and the implementation of universal childhood vaccination programs. Although the century began badly with the terrible emergence of the 1918 influenza pandemic, also known as Pneumonic Plague or Spanish Flu, and later with the epidemics of typhus, smallpox, and diphtheria that arose as a consequence of poor sanitary conditions after World War I, as time progresses, chronic diseases are becoming the leading cause of death and illness in our society.
Let's take obesity as an example. In 1920, the consequences of obesity on population health were first described through the analysis of records from the Metropolitan Life Insurance Company. Later, throughout the 20th century, much information was gathered linking obesity to other pathologies such as diabetes and, later, hypertension. Progress was slow at first. In the case of obesity, it only became a political issue and a matter of public discussion in 1973, when George Bray produced the famous Fogarty Report in the United States. And it was only in 1988 that the WHO published its first "Nutrition and Chronic Disease Report for the European Region" with a separate chapter on obesity.
It was at the end of the 20th century, starting in 1976/77, that the training of nutritionists began in Portugal, more specifically through the University of Porto. Nutritional sciences and the Porto School of Nutrition thus grew, alongside the increase in knowledge about nutrition and chronic diseases, and also alongside the unstoppable growth of these diseases in Portugal. In 2015, the prevalence of diabetes in the Portuguese adult population between 25 and 74 years old was approximately 10%. The prevalence of hypertension was 36% and the prevalence of obesity was 29%. In this context, it was estimated that 5.9 million Portuguese people were overweight, the same being true for 8 out of 10 elderly people. This public health crisis, in an elderly population chronically ill from a very young age, has forced an excessive expenditure of resources in the National Health Service in recent years.
The emergence of chronic diseases and the concentration of resources in combating this problem has, to some extent, obscured the growing risk of new forms of infectious disease in Europe, and also in the rest of the world. Due to numerous success stories, such as the polio vaccination campaign, the last case of which dates back to 1986, or the success of the National Measles and Rubella Elimination Program, which led Portugal to obtain certification of measles elimination from the WHO-Europe in 2015 and 2016, the National Health Service has established an effective structure that has reassured us in this regard.
However, we cannot be deluded by this success. The existence of a network of sensors and alerts for infectious diseases is not enough for a country to consider itself prepared to face an infectious outbreak. A new infection translates into the appearance of a microorganism with different characteristics, which may have new transmission mechanisms, with an unknown viral load and unknown health consequences that prevent an immediate response. When the contagiousness is high, the responses to the unknown, even in the current improved system of communication between the international scientific community, revert to the old responses to pandemics through isolation and quarantine as applied since the Middle Ages.
While viruses (more specifically the coronavirus family) are not entirely new, what is truly new in this context is the economic, demographic, social, and political situation in the 21st century. When, at the beginning of the 20th century, in 1918-1919, a new pandemic, the Spanish Flu, affected Europe and Portugal, malnutrition, lack of hygiene, and overcrowded medical camps and hospitals throughout Europe (as a consequence of World War I) were perhaps the factors that most exacerbated its mortality. In Portugal, the Spanish Flu caused 136,000 deaths in a country with six million inhabitants, one of the highest mortality rates in Europe. Although we are now in the 20th century, it is worth remembering that the average life expectancy at birth in Portugal in 1930 did not exceed 45 years for men, which was one of the worst figures in Europe. At the same time, the Portuguese infant mortality rate in 1930 was 144 deaths of children under one year of age per thousand inhabitants. Among the main causes of death were diarrhea and enteritis (the direct cause of 14% of deaths between 1934 and 1940) or tuberculosis (the cause of 10% of deaths in the same period). In 1918, there were several parallel epidemic outbreaks of smallpox, typhoid fever, typhus, and dysentery.
On September 5, 1899, Ricardo Jorge wrote in his diary: “Porto lacks a good sewage system, and the filth in the city's lower neighborhoods is indescribable and sufficient to cause any epidemic. (…) It is now necessary to take very energetic measures, to build new sewers, or, without this, Porto will continue to be one of the most unsanitary cities in Europe.” In 1918, the situation had not improved. At that time, Ricardo Jorge, already as Director-General of Health and director of the Central Institute of Hygiene, described in a report the situation of the Porto islands in the face of the typhus epidemic, “the disease has a predilection for the lowest classes, poorly housed, mistreated and poorly maintained.” In 1930, the percentage of illiterate people among the population over 7 years of age reached 62.3%, and agricultural work occupied more than half of the active population. It is therefore not surprising that this pandemic had such a high fatality rate and eventually so little media attention in a climate of high mortality, malnutrition and daily unsanitary conditions in our communities.
A modern society, chronically ill but ill-prepared for infection
Currently, the situation is very different. Starting with the advancement of our medicine and our installed capacity. In 1920, there were 2580 doctors in Portugal, suggesting one doctor for every 2338 inhabitants, while currently there is one doctor for every 189 inhabitants (2018 figures for the mainland). At the beginning of the 20th century, many doctors were enlisted and serving in the armed forces, thus preventing them from serving the general population. Additionally, medical assistance and even access to pharmacies was extremely scarce in the interior of the country, areas where almost half of the Portuguese population lived. Currently, the distribution of healthcare personnel and hospital units is concentrated on the coast, where the majority of the population resides, and the sanitation situation in our cities is completely different. The demographic and social situation has also changed substantially. Today, less than 6% of the active population works in the agricultural sector. To give an idea of the speed of this evolution, the number of people belonging to farming households fell from almost 2 million in 1989 to about 800,000 in 2009, representing a 60% drop. In 2011, only 6% of the population over 15 years of age was illiterate, and 62.2% of the population (6,566,925 inhabitants out of a total of 10,562,178 inhabitants) lived in cities or urban areas.
This trend towards population concentration in urban areas has been intensifying in recent decades, with a reinforcement of larger population centers at the expense of smaller ones. In other words, the processes of coastalization and metropolization continue around large urban areas such as Porto and Lisbon. These are nothing more than a utopian promise of economic and political emancipation and a place of integration for people of different origins who seek freedom and personal affirmation in large cities.
Alongside urban concentration along the coast, the aging of the population is also a notable trend. Changes in the size and distribution by sex and age of the resident population in Portugal, due to low birth rates and increased longevity in recent decades, indicate, in addition to population decline, the continuation of demographic aging. In 2018, the young population (people under 15 years old) decreased to 1,407,566 people, and the population aged 65 or older increased to 2,244,225 people, representing 13.7% and 21.8% of the total estimated population, respectively. In 2018, half of the resident population was over 45.2 years old, and Portugal had one of the oldest populations in the world. In 2008, for every 100 young people living in Portugal, there were 116.4 elderly people, a number that increased to 159.4 in 2018. In addition to having an aging population, we also have a very sick population.
Illness naturally accompanies aging, but in our national context, we spend more years ill than the European average. In 2018, in the European Union, it was expected that men over 65 would live 9.8 years of healthy life and women 10.0 years of healthy life (with "unhealthy life" considered to be the limitation in activities normally performed by people due to health problems during the previous 6 months). In Sweden, these values reached 15.6 years for men and 15.8 for women in 2018. In Portugal, in that same year, it was expected that men would live only 7.8 years of healthy life and women 6.9 years of healthy life after the age of 65. These values become even more pronounced when considering the high longevity of our population, as our life expectancy is high and above the European average. In other words, we are one of the European populations that lives the most years… ill. Patients with chronic conditions, many of which are diet-related, such as diabetes, cardiovascular disease, respiratory disease, obesity, and cancer.
But if chronic diseases are responsible for 80% of mortality in European countries, and Portugal is no exception, the prevalence of these diseases is conditioned by individual and social risk factors. That is, factors that we could modify, such as excess weight and inadequate eating habits, sedentary lifestyle, smoking, and alcoholism. According to the "Global Burden of Disease," about 41% of the total years of healthy life lost due to premature death in Portugal could have been avoided if these risk factors were eliminated. These diseases have a high social gradient. For example, the most recent national health survey with physical examination, conducted in 2015, identified that the group of individuals who had no schooling, or who only had primary education, had a prevalence of obesity (43.1%) more than double that of groups of individuals with higher education (higher education). The same trend occurred for hypertension and diabetes, for example.
This current infectious outbreak has caught Portugal off guard, a country with an aging population, a high prevalence of chronic diseases (overweight, diabetes, and hypertension), and a population concentrated along the coast and in densely populated cities. As has been demonstrated, viral infectious diseases preferentially affect people with certain chronic conditions such as obesity. This is because several steps in the innate and adaptive immune response are altered due to the low-grade chronic inflammation present in obesity, diabetes, and metabolic syndrome. This explains why obese individuals exhibit elevated levels of pro-inflammatory adipocytokines such as leptin. This alteration of the hormonal environment leads to changes in the immune response, contributing to the pathogenesis of complications associated with obesity. Unlike past pandemics, the current epidemiological situation will make those with chronic diseases, and in particular obesity, the most susceptible to infectious diseases. The same pattern repeats itself: it is always the most vulnerable members of society who are most exposed to illness. If in the Middle Ages it was the poorest people, hungry and malnourished, today it is equally the poorest, only this time those affected by the modern malnutrition that is obesity.
With continued population growth, the concentration of people in urban centers, the maintenance of aging social and demographic profiles, and the persistence of the epidemiological profile caused by excess energy and sedentary lifestyles, it is natural that waves of infectious diseases will continue to mix with and exacerbate chronic diseases already present in our society. And if social isolation is a trend in combating these diseases, it is natural that chronic diseases and the consequent metabolic dysregulation will also tend to increase.
A new world, more socially unequal and experiencing an environmental crisis
What is truly new is that this new mix of acute/chronic illness brings a new need for physical containment that did not exist in the past. If obese, hypertensive, or diabetic individuals had a relatively "immobile," non-transmissible disease, when we add infectious disease to this equation, these people add mobility and potential transmissibility to the disease. They thus become a factor in its spread, and their isolation is a natural strategy to combat the disease and protect themselves. Now, the isolation of chronically ill patients also means, and especially in Portugal, the isolation of people with lower levels of education, lower incomes, and also those in professions involving physical contact, with reduced capacity for teleworking and lower economic capacity, which tends to exacerbate the stigma, social inequalities, and health inequalities already existing in our society.
It is worth noting that the economic situation was already a strong determinant of food consumption patterns. We know that economically more vulnerable populations are also those with less access to fresh food, and where the price/calorie supply ratio tends to favor the consumption of processed products with high energy density, preserved with salt and sugars. These products keep better on shelves, are heavily promoted commercially, and are available 24/7. To worsen this situation, we should note that in the context of infectious disease outbreaks, there is a tendency, even if more or less temporary, for the breakdown of solidarity and voluntary food supply networks. Consequently, the supply of low-quality, cheap food products that keep well but are only available during times of crisis increases, tending to exacerbate metabolic imbalances. This metabolic imbalance is a risk factor precisely for chronically ill patients facing viral infectious diseases.
In parallel, infectious outbreaks are intense shapers of healthcare service delivery. On these occasions, healthcare services tend to divert resources to the treatment of acute illness, momentarily neglecting chronic disease, which is curiously the most affected by acute illness and also the one that can increase mortality from the infectious disease itself.
This crisis is also not independent of the ecological crisis we are experiencing. We have already discussed the concept of "syndemic," that is, a synergy of pandemics that coexist in time and space, interact with each other, and share common social and other factors. This concept was first used by Merrill Singer and Scott Clair in 2008 in the report "Syndemics and Public Health: Reconceptualizing Disease in Bio-Social Context" to explain the synergy between epidemics of malnutrition (obesity and undernutrition) and climate change. Two global-scale problems of a complex nature, with common social causes and determinants, and with consequences for human and planetary health. Both the origin and the difficulties encountered in halting the progress of these different pandemics have common causes. To this we can now add the Covid-19 pandemic, which is nothing more than a mixture of high population density and interconnectedness, invasion of animal ecosystems, malnutrition and metabolic imbalance in a large part of the population, economically unprotected and, moreover, aging. These are conditions that climate crises tend to exacerbate.
The role of the nutritionist in the post-COVID world
In this context of a paradigm shift in public health intervention, the continued centrality of adequate nutrition as a determining factor in maintaining the health status of populations is evident, as is access to this same adequate nutrition as an important factor in reducing health inequalities. However, while the adequacy of and access to healthy food will remain central to promoting population health, the nutritionist's intervention model will now have to be more adaptable to this new situation.
First, it will be necessary to combat the previous idea of a certain independence or separation between chronic and acute diseases. As we have noted, these are categories of disease that, in the current context of COVID, end up interrelating and amplifying each other. Nutrition for reducing inflammatory processes, maintaining a healthy immune system, and metabolic control have much in common and should not be separated. These processes are vital in preventing or mitigating future outbreaks of infectious diseases, and community nutritionists will play a central role in these interventions, during and between future crises, or between waves of the same pandemic. More specialized interventions in combating infection will also increasingly require professionals capable of providing adequate nutritional support in more specialized healthcare units, and therefore this is an area that will require our utmost attention.
The same will happen with training for remote care by healthcare professionals, requiring a necessary revision of some codes of ethics and a less conservative, more rapid and adaptive approach from the profession's regulatory bodies, namely the professional associations
But other challenges will arise. In society, and in Mediterranean society in particular, mealtimes are moments of conviviality that are important for the emotional well-being of populations, for a more balanced diet, and also for reducing the environmental impact of food consumption. Nutritionists will be responsible for developing new food safety regulations while maintaining minimum standards of conviviality. This intervention will be even more important in high-risk areas such as those where institutionalized patients or elderly people live. Food production and distribution systems will increasingly try to utilize local production and autonomy models in response to market needs. New systems will need to be designed. After the widespread adoption of the Hazard Analysis and Critical Control Points (HACCP) system, aimed at preventing potential risks to consumers by providing safe food through Regulation (EC) No 852/2004, it is time to revisit the critical points of these systems, with the new concern being infection among professionals in the food chain.
All these models, whether for healthcare provision or the food production system, now stem from a new paradigm highlighted by this crisis. The less human involvement, the more robust the production chain becomes and the less susceptible it is to unscheduled interruptions. In other words, we will be increasingly asked to design food production, healthcare, and control models that will increase unemployment in more traditional areas of nutritionist intervention in the future. Nothing that Isaac Asimov's dystopian work didn't foresee back in the 1940s. The theme of human dependence on robots capable of creating superior robots, and so on, until machines become such complex mechanisms that they escape human verification and control. Robotization is certainly a process that these diseases will accelerate, including in the food chain and in the workplace.
Nutritionists should participate in these rearrangements so that this investment does not deprive the most economically disadvantaged population of access to healthy food products. The most economically disadvantaged and malnourished populations (due to excess or deficiency) will be the first to need quality food support in this and future infectious disease outbreaks. Food shortages will appear. At the very least, the scarcity of healthy products for the most vulnerable will be felt, and food insecurity will once again exceed 2011 levels. Training and education for emergency food support while maintaining nutritional quality will certainly be one of the areas of training for nutritionists in the future. This will also include combating the stigma surrounding those infected in the first phase, and those with chronic illnesses and the elderly, who will be the groups most affected by this interaction between infection, chronic disease, and poverty, as a determinant of the time and use of human and physical resources of health systems.
Epilogue
Almost at the end, let's return to the beginning. For centuries we fought plagues without experimental knowledge, based only on empiricism or religious dogma. Despite everything, the "nutritionists of yesteryear" were always on the front lines. They banned foods like "chicken, fatty meats, or olive oil" in medieval anti-plague manuals, or suggested foods and ways to design cities to combat the disease, as Leonardo da Vinci, a food fanatic during the plague of 1484/1485, did. Today, knowledge is different, and we know how we can be useful on the front lines, whether in combating malnutrition and associated diseases like diabetes or in combating infectious diseases like COVID-19. The tools are also different, but the foods are the same. Most likely, the foods that have protected us for the last 8,000 years throughout the Mediterranean basin are the same ones that will be crucial in combating metabolic dysregulation and promoting immune system optimization. And, at the same time, preserving the environment.
The risk society we currently live in, as presented by the German sociologist Ulrich Beck, has progressively ceased to have as its central concern the fight against scarcity (food, among other basic needs), subtracting from the modernization process its previous basis of legitimacy: the fight against evident scarcity, for which some of its secondary effects were acceptable. Current society will now be characterized by new risks. These risks are mostly invisible, being established by knowledge, which can dramatize or minimize them, and susceptible to social processes of definition, where whoever defines the risk becomes a crucial socio-political actor. This type of risk also affects those who produce it and those who benefit from it, in many cases being global risks, producing new types of inequalities, where knowledge acquires a new political meaning. The fact that these risks have increasingly fewer borders, and that public and political opinion may be unwilling to accept them, leads to increased public and political interference in the sphere of individual and even national autonomy.
However, we may find good things in this crisis. The private idea of happiness that was becoming predominant and that had ceased to be associated with collective projects may have been rethought by some during these weeks. Our current destiny seemed to be, in the words of Daniel Innerarity, "every man for himself amidst impersonal forces stemming from globalization, bureaucracy, and technology, in a society without politics, without collective hope, incapable of imagining and promoting an alternative common future." This crisis may have helped to understand, at least a little, that public policy can be the effort to transform fatality into responsibility. And quoting Innerarity again, "One of the things in our democratic tradition that most deserves to be protected is precisely the rejection of fate. The future depends more on our decisions and commitments than those who elaborated the modern idea of progress as an irresistible force to which we could confidently surrender thought.".
The solution is once again in our hands. And our professional action will now be more decisive than ever. In fact, nutritionists cannot "stay at home" in these times, at the risk of becoming irrelevant. We need the people of science and also the contribution of nutritional sciences so that it is shared knowledge and community civic-mindedness that win this "war," and not authoritarian regimes and their security measures that promote the erosion of the rights and freedoms of populations.
Written by
Pedro Graça, Director of the Faculty of Nutrition and Food Sciences at the University of Porto