Junk food increases the risk of COVID

Junk food increases COVID risk


A study reports that people who regularly consume ultra-processed industrial foods are at greater risk of being infected with the coronavirus responsible for COVID-19. 

COVID-19 continues to pose a threat to public health and the economy around the world, not to mention that many survivors of the disease must deal with its long-term negative effects, which can persist for several months after infection (COVID long).  

The emergence of new variants capable of partly escaping the antibodies developed in response to vaccines also means that the most vulnerable people remain at high risk of being infected and develop serious forms of the disease that can be life-threatening.  

This vulnerability is particularly pronounced in the elderly, as well as in those affected by preexisting chronic conditions (comorbidities) or poor metabolic health (obesity).  

The pandemic is not therefore not yet finished and every action that can reduce the risk of infection (booster doses, basic hygiene) remains important to protect those most at risk.

Immune health

A healthy immune system is a rarely talked about aspect of fighting infection. However, like all cells in the body, immune cells must rely on an optimal environment to function properly. 

This good immune health is inseparable from good health in general and can therefore be achieved at using the five main pillars of good health, namely not smoking, sleeping well, exercising, maintaining a normal body weight and adopting a healthy diet.

Eating well immunity

A high-quality, plant-rich diet appears to be particularly important for immune health. These foods meet the nutritional needs of immune cells (nutrients, vitamins, minerals) while promoting the establishment of a diversified intestinal microbiome, essential for the education and proper functioning of the immune system.  

As a result, a high plant intake is associated with a reduced risk of several infectious diseases, including COVID-191.  

On the other hand, several studies suggest that a poor diet negatively influences the effectiveness of the immune system. This is well illustrated by the results of a study that looked at the link between ultra-processed industrial foods (industrial ready-to-eat products, fast food) and the risk of COVID-192.

In this study, researchers analyzed the eating habits of 41,012 participants (mean age 56) who participated in the UK Biobank study and assessed the association between the amount of ultra-processed foods consumed (as % of daily calorie intake) and a diagnosis of COVID-19. 

They observed that compared to participants who ate these foods infrequently, those who ate them regularly had an approximately 25% risk of infection. % higher.  

According to the researchers' calculations, part of this association (about 15%) is due to the higher body mass index of regular consumers of ultra-processed foods, while the rest is a consequence of the nutritional poverty of these products as well as their pro-inflammatory effect.  

In this sense, it should be mentioned that one of the consequences of this inflammation is to modify the composition of the gut microbiome and to increase the permeability of the intestinal barrier to different pathogenic organisms.  

This is important in the context of COVID, as a recent study has shown that infection with the coronavirus significantly alters this microbiome and increases the risk of secondary bacterial infections3.  

The The combined effect of a diet high in ultra-processed foods and COVID may therefore create a climate conducive to the development of these opportunistic infections.

In short, in addition to being associated with an increased risk of colorectal cancer, cardiovascular disease and premature mortality, ultra-processed foods could also increase the risk of infectious diseases such as COVID-19.  

These results show once again how what we eat can influence our health in general, including that of our immunity. 

1. Deschasaux-Tanguy M et al. Nutritional risk factors for SARS-CoV-2 infection: a prospective study within the NutriNet-Santé cohort. BMC Med. 2021; 19:290.
2. Zhou L et al. Impact of ultra-processed food intake on the risk of COVID-19: A prospective cohort study. Eur. J. Nutr., published August 16, 2022.
3. Bernard-Raichon L et al. Gut microbiome dysbiosis in antibiotic-treated COVID-19 patients is associated with microbial translocation and bacteremia. Nat. Commun., published November 1, 2022.