Since time immemorial, humankind has needed to transmit to those closest to them a set of information about what to eat and when to eat. This was a matter of survival. A contaminated water source or a mushroom out of place could decimate part of the group and jeopardize the lives of all. This information was later written down, and whoever possessed it held considerable power. This knowledge quickly translated into canons that allowed for social, economic, and religious dominance. One need only recall the Old Testament or Hebrew Bible, specifically the book of Leviticus , which provides a lengthy description of clean and unclean animals and a large set of rules about how and who can handle these categories of food. These dietary rules still persist in the major monotheistic religions today. The idea of identifying food hazards, contaminants, and other risks to the existence and eventual hegemony of groups has become the norm in these last few thousand years. According to experts like Samuel Paul Veissiere, humans have this negativity bias and "tend to be obsessed with anything that conveys information about potential threats for obvious survival reasons." He states, "Human cognition works this way; people pay more attention to negative information, remember it more, and feel more motivated to pass it on to others. And we see a lot of this on the internet now that people are interconnected all the time. So that's the general kind of evolutionary structure .
This communication model, heavily influenced by "negativity bias," has been refined over centuries of epidemics, particularly as human settlements grew in size during the Middle Ages and the most deadly plagues emerged. The Black Death in the 14th century is an example of this event, which had a major impact on the population (it is estimated to have killed at least one-third of the European population, particularly between 1346 and 1353) and still influences our thinking and actions today. Later, the Great Plague of Lisbon in 1569 is estimated to have killed 600 people a day; a total of 60,000 inhabitants of the city are believed to have succumbed.
In all these cases, plants and dietary habits were of great significance to the populations. The prophylactic measures recommended by the University of Paris in 1348 included fumigating homes with chamomile flower incense, as well as squares and public places. People were advised to abstain from eating chicken or fatty meats and olive oil. Bathing was considered dangerous and sexual relations fatal. Recommendations were made about what one could not do or eat, based on beliefs and without credible knowledge, often spreading incorrect information that contributed, in many cases, to worsening the sanitary situation.
Today, in the 21st century, the circulation of poor-quality information continues to be a decisive factor in the unfolding of modern epidemics, whether viral or due to the excessive consumption of certain foods. Therefore, we can affirm that there is a relationship between this public health crisis caused by SARS-CoV-2 and public health issues related to food and nutrition. Not so much because food can prevent or cure this new disease, but more because of the similarities between those who analyze and discuss the subject.
Those who have worked in the field of nutritional sciences for some time have observed the almost exponential proliferation of content about nutrition in the media and, later, on social networks. The reasons are multiple, ranging from the growth of published science to the interest of citizens, who are increasingly concerned about this association between health and food. On the other hand, although nutritional knowledge deserves the same rigor as other scientific fields, daily interactions with eating practices (we all eat) and the cultural aspects associated with our diet (we are all exposed to them) seem to lead to widespread nutritional beliefs based on occasional scientific studies and popular intuition, rather than on solid science. And to the emergence of a wide variety of commentators and pseudo-experts in nutrition who, every day, support the most varied theories and solutions to problems in the area. Now it's the turn of virology. At the present moment, and because we all have access to some information and experience the problem very closely, experts in epidemics are also emerging in great profusion. In these times of crisis, it seems necessary to talk. Almost out of natural necessity. As the philosopher José Gil says in his recent essay on fear, "Communicating with others and with the community is to break the bubble, to expand the limits of space and time, to become aware that our world extends far beyond the rooms to which we are confined . Unfortunately, and as is the case in Nutritional Sciences, the solution to most problems lies in common sense, knowledge, awareness, and individual decision-making, not in easy, quick solutions that others can make for us.
In the relationship between SARS-CoV-2 and diet, there are no magic solutions, and anyone who claims otherwise, based on the current state of scientific knowledge, may not be guided by the best scientific evidence. After contact with the virus, most people develop mild illness, with the likelihood of serious complications being more common in older age groups, those with other chronic diseases (e.g., diabetes), or those with weakened immune systems. Scientific evidence is scarce regarding the relationship between diet and strengthening our immune system. We know that, in general, adequate nutritional and hydration status contributes to an optimized immune system. Thus, although there is probably no single food, nutrient, or supplement capable of modifying the course of the disease as a whole, a diet that follows the rules of the Food Pyramid and maintains good nutritional status may make a difference compared to those who do not follow it.
The role of nutritionists is therefore to communicate simple messages. And to help preserve the supply chain by informing people about the need to avoid buying poorly and in excess. To promote a balanced diet in the many children who will reduce their physical activity, so that childhood obesity does not increase in these weeks. And to help those who are debilitated and hospitalized recover, contributing to adequate nutritional support on a case-by-case basis. We hope that common sense will prevail in the area of food. And that nutritionists will contribute their scientific knowledge to informed decisions by citizens in these times of concern and anxiety.
Note 1 – The current health situation allows us to deviate from some editorial guidelines common in other Pensar Nutrição articles.
Note 2 – The authors thank Professor Nuno Borges and Professor Alejandro Santos for their contributions to the production of this text.
Photo by Fusion Medical Animation on Unsplash
