Both the health emergency caused by the COVID-19 pandemic and the situations generated by previous viral pandemics have shown that there is a close interaction between infectious diseases and non-communicable diseases (NCDs) (1, 2, 3).

Unhealthy eating patterns represent the first behavioral risk factor linked to mortality and disease burden in Latin America and the Caribbean (4). These patterns are mainly characterized by the habitual and excessive consumption of ultra-processed foods and beverages, defined as industrialized products made from components extracted from food, with the presence of additives and high contents of critical components such as free sugars, saturated fats, and sodium (5).

Mathematical and epidemiological models have estimated that the COVID-19 pandemic could last until the end of 2021 (6) or even longer (7). This article documents the interactions between viral pandemics, such as that generated by SARS-CoV-2, and NCDs. It also raises the need to implement political actions to promote healthy eating and reduce the consumption of ultra-processed foods, not only to prevent various forms of malnutrition but also to avoid further deterioration of the clinical conditions of people suffering from them.

This article assumes that healthy eating should be complete, balanced, sufficient, and adequate. These criteria are relevant in light of current public health situation. In general, healthy eating should be complete, based on the daily consumption of natural or minimally processed healthy foods that promote a varied diet in homemade and traditional preparations. The diet should have a balanced proportion of nutrients to allow for maximum utilization. In addition, to promote an optimal quality diet, the amount consumed should be sufficient to provide the energy requirements and nutrient needs of each person. In addition, food should be appropriate for the age, tastes, and habits of people, safe and in long-term harmony with the environment. This is summarized by José Buschini (8), in his book La alimentación como problema científico y objeto de políticas públicas en la Argentina (Food as a scientific problem and object of public policies in Argentina).

Processes linked to global climate change, which affect animal reservoirs and migration patterns of various birds, could increase the spread of new influenza virus strains (9). The threat of viruses with pandemic potential in humans and animals has increased in recent decades, due not only to the growth of human, poultry, and swine populations but also to the effects on the ecology, which increase the interaction between humans and wild species (10, 11).

The expansion of the agricultural frontier and deforested areas in several regions of the world inevitably generates an increase in the frequency of virus exchange between natural reservoirs and humans (10,12). In this context, the challenge for human societies is to halt the processes of agricultural expansion and deforestation, while identifying promptly not only the virus strains that are transmitted and generate disease in humans, but also those that spread efficiently among humans (10,13,14).

There is a documented link between NCDs and the severity of viral pandemics in Latin America. A study conducted in Mexico in 2009 during the H1N1 influenza pandemic found that 40% of patients had metabolic syndrome, 21% had cardiovascular disease, 20% had diabetes, 20% had high blood pressure, and 38% of women and 26% of men were obese (15). Another study in the same country reported that 36% of critically ill patients requiring intensive care unit management were obese (16).

Similar results were found in other Latin American countries. In Brazil, 38% of patients diagnosed with severe influenza A (H1N1) pneumonia were obese, and 36% had one additional risk condition linked to the severity of the disease, with diabetes being the most frequent (21%) (17). A study conducted in Chile found that 33.3% of the patients who died were obese, compared to 6.1% of those who survived (18). Another Chilean study reported that 47.1% of patients with H1N1 were obese. When comparing obese and non-obese individuals, the first subgroup had a higher chance of having two or more comorbidities (OR: 8.2; 95% CI: 3.8-17.9; p < 0.0001); this group also required more mechanical ventilation and vasoactive drugs and had more complications, with statistically significant differences. Furthermore, mortality was higher in obese patients than in non-obese patients (36% vs. 19.4%) (19). Finally, according to an Argentine study, 67% of patients had one or more pre-existing medical conditions. Of the patients who died, 86.4% had comorbidities compared to 57.1% of the patients who survived. The most frequent diseases in the group of patients who died were obesity (40%), diabetes (19%), cardiovascular disease (15%), and arterial hypertension (38%) (20).

Regarding the COVID-19 pandemic, evidence indicates that patients diagnosed with this disease and whose clinical picture progresses to severe pneumonia, acute respiratory distress syndrome or death have higher proportions of chronic conditions such as hypertension, diabetes mellitus, and cardiovascular conditions (21). These findings suggest that NCDs are risk factors linked to clinical severity in patients diagnosed with COVID-19 (22).

These results are consistent in different countries. Thus, a systematic review carried out from information obtained in China up to March 2020 found that patients with severe clinical pictures caused by COVID-19 were 2.3 times more likely to have been previously diagnosed with hypertension than those with mild or moderate clinical manifestations (OR: 2.3; 95% CI: 1.4-3.8). For chronic respiratory disease and cardiovascular disease, the odds were 2.4 and 3.4, respectively (OR: 2.4; 95% CI: 1.7-3.4 and OR: 3.4; 95% CI: 1.8-6.2) (23).

The high frequency of chronic comorbidities has not only been documented in older adults. A study conducted in 14 U.S. states found that 59% of patients hospitalized in March 2020 for COVID-19, aged 18-49 years, had obesity, 19.6% had diabetes, 17.5% had high blood pressure, and 36.4% had chronic respiratory diseases such as asthma and chronic obstructive pulmonary disease (24). Similar results have been reported in the New York metropolitan area (25). These percentages are higher with respect to prevalence reported in the general U.S. population of similar ages (26, 27, 28).

Regarding links with obesity, in France, the proportion of COVID-19 patients requiring invasive mechanical ventilation increased as a function of body mass index (BMI) categories. Patients with a BMI greater than 35 kg/m² were 7.4 times more likely to require invasive mechanical ventilation than those with a BMI less than 25 kg/m² (29). Additionally, in New York, it was found that patients hospitalized for COVID-19 under 60 years of age who were obese were 2 times more likely to be admitted to an intensive care unit in contrast to those who were not obese (30). These findings are similar to those of a study in Italy and could indicate that COVID-19 mortality is significantly higher than in China, due to the lower prevalence of obesity in the latter country (31).

According to the Global Burden of Disease Study (32), the percentage of deaths attributable to NCDs in Latin America and the Caribbean increased from 57.4% in 1990 to 75.6% in 2017. Regarding the estimated burden of disease in disability-adjusted life years (DALYs) attributable to NCDs, the proportions were 47.5% and 68.6% in the same period (33).

Countries classified by the World Bank in the upper-middle-income category, like most countries in the region, have a significantly higher burden of hypertensive heart disease relative to high-income countries (34). This pattern persists even in people who do not belong to the older adult group. According to the Global Burden of Disease Study, the rates of DALYs per 100,000 population attributable to hypertensive heart disease in persons aged 50 to 69 years in 2017 was 453 in Latin America and the Caribbean, and 129 in Western Europe (34). In the case of diabetes mellitus, the rates were 3,570 and 1,318, respectively (35).

The growing problem of NCDs is mainly explained by unhealthy eating patterns, physical inactivity, and tobacco use (4). Both caloric intake of unhealthy foods and physical inactivity are closely related to obesity, which considerably affects all countries in the region, with prevalence exceeding 30% in the adult populations of Mexico and Chile (36, 37).

In low-income countries, the association between socioeconomic status and obesity is positive in most cases; that is, the higher the socioeconomic status, the higher the prevalence of obesity. However, in middle-income countries, such as most Latin American countries, the relationship is negative in the female population, which means that poorer women are more likely to suffer from obesity (38). In Argentina, Bolivia, Colombia, Brazil, and Paraguay, adult women with educational levels higher than high school were less likely to be obese, in contrast to those with lower levels of education (39). It is predictable that, in the context of globalization, obesity, diabetes, and arterial hypertension will be increasingly concentrated in the most socially vulnerable population in Latin America.

People living in vulnerable conditions have social, economic, and political constraints, which prevent them from making appropriate decisions regarding their dietary patterns. Several studies have found that belonging to a low socioeconomic stratum is positively associated with unhealthy eating patterns (40, 41, 42).

Documented experiences in epidemic outbreaks of Ebola and Middle East respiratory syndrome show that these types of emergencies affect food production and supply chains (43, 44). During these epidemics, food insecurity increased, affecting mainly children, women, and the elderly in the most socially vulnerable sectors. In the Ebola epidemic that occurred in several West African countries in 2014-2016, prices of staple foods such as rice and cassava increased by 30% and 150%, respectively (45).

The humanitarian crisis being caused by the COVID-19 pandemic has large-scale negative economic consequences and affects the supply and consumption of unprocessed foods with high nutritional value. Regardless of the future scenario regarding the behavior of the pandemic, the poorest population and the most socially vulnerable human groups will be the most affected, because they have fewer resources to cope with the loss of jobs or income and the likely increase in food prices (46). This is a particularly critical situation in the Venezuelan migrant population living in conditions of poverty (47). Vulnerable populations face challenges in protecting themselves from disease, have no income, belong to the informal economy, and lack flexible work schemes (48).

In the absence of a socially adequate response through the State, the prevalence of forms of malnutrition such as acute malnutrition, chronic malnutrition, and micronutrient deficiencies may increase, due to the decrease in supply and low consumption of foods with high nutritional value. For example, ill-conceived government food assistance programs and food bank initiatives would lead to increased consumption of ultra-processed foods and increase the burden of disease attributable to chronic non-communicable conditions. Evidence from food banks suggests that most of these programs provide foods of low nutritional quality (49).

From this evidence and from studies that have evaluated the short-term cardiometabolic effects of unhealthy eating patterns (50, 51, 52), it is plausible to think that unwise political decisions in food assistance programs aimed at the most socially vulnerable population would aggravate the clinical conditions of patients with NCDs and increase the likelihood of death if they acquire COVID-19.

Political actions that ensure the supply of unprocessed foods of high nutritional value to markets on a regular and timely basis and that allow farmers to continue to cultivate and harvest are a key pillar in mitigating the indirect negative health effects of the pandemic (43). For this purpose, it is necessary to implement the following recommendations:

Ensure the adequate nutritional quality of financial or in-kind contributions. To this end, Unicef recommendations (54) emphasize that neither breast milk substitutes nor donations of foods with excessive content of free sugars, sodium, or saturated fats should be accepted. This recommendation should be extended to all ultra-processed foods (55). Also, avoid in-kind donations or financial contributions from industry sectors that produce unhealthy foods. This type of contribution by the industry seeks to promote joint communications with the public sector to promote a positive corporate image before society (54).

It will not be possible to mitigate the potentially devastating effect of future viral pandemics if strong action is not taken to prevent the risk factors for NCDs. After the pandemic, it is not possible to return to what was assumed to be “normality”, characterized, among other aspects, by a negative environmental impact associated with production, distribution, and commercialization processes, as well as by a high and growing consumption of ultra-processed foods (59).

In this context, a comprehensive approach is required to address the growing challenge of obesity and NCDs associated with unhealthy eating patterns, including the following actions: taxes on sugar-sweetened beverages, restrictions on marketing and advertising of and ultra-processed beverages and foods, consumer-friendly front-of-pack labeling, as well as policies to modify agricultural and food systems (60). A public policy that integrates these actions will gradually prevent new cases of obesity and potentially decrease the percentage of obese people in the long term, leading to a reduction in the accumulation of risk that can mitigate other large-scale infectious events. These political actions have the potential to prevent different forms of malnutrition, which include not only overweight and obesity, but also malnutrition, micronutrient deficiencies, and unhealthy eating patterns (61).

To achieve these goals, it is necessary to transform agricultural and food systems, based on the following criteria:

Focus social protection programs not only on promoting the production and consumption of unprocessed or minimally processed foods but also on preventing food insecurity (62).

The emergency generated by the COVID-19 pandemic highlights the need to strengthen public health institutions, not only to address infectious diseases but also to implement political actions aimed at preventing NCDs. The interaction between the clinical severity of viral pandemics such as COVID-19 and H1N1 and NCDs highlights the urgency of a comprehensive approach that includes short- and long-term actions.

Political actions aimed at promoting healthy eating and discouraging the consumption of ultra-processed beverages and foods are a key component in promoting appropriate dietary patterns and addressing this challenge.

In Latin America, the agents responsible for input supply, logistics, and food processing and retailing are expected to be the most affected by the disruption of domestic trade (53). The availability of healthy, locally produced foods is essential to promote their consumption and reduce the purchase of ultra-processed food products. For this reason, it is necessary to ensure production, distribution, and access to healthy foods during and after the pandemic.

The authors declare that they have no conflicts of interest.