Obesity and COVID-19: What are the Consequences?

Abstract

Obesity is an increasing health problem all over the world. In combination with the current COVID-19 pandemic, this has turned into a massive challenge as individuals with overweight and obesity at all ages show a significant increase in their risk of getting severe COVID-19. Around 20% of all patients that were hospitalized for COVID-19 suffered from obesity alone, whereas obesity in combination with other metabolic comorbidities, such as type 2 diabetes and hypertension, account for up to 60% of all hospitalizations in relation to COVID-19. Therefore, it is of immense importance to put the spotlight on the high incidence of obesity present already in childhood both by changing the individual minds and by encouraging politicians and the whole society to commence preventive interventions for achieving a better nutrition for all social classes all over the world. In the current review, we aim to explain the different pathways and mechanisms that are responsible for the increased risk of severe COVID-19 in people with overweight and obesity. Furthermore, we discuss how the pandemic has led to weight gains in many people during lockdown. At the end, we discuss the importance of preventing such an interface between a non-communicable disease like obesity and a communicable disease like COVID-19 in the future.

Fig. 1

Chronic inflammation in adipose tissue of obese individuals: There are several reasons why obesity can lead to a severe course of COVID-19. One possible cause is the chronic inflammatory reaction in the adipose tissue. In adipose tissue with hypertrophic adipocytes, there is a mass production of pro-inflammatory cytokines, such as IL-6, IL-1β, and TNF-α. In addition, more and more immune cells invade the adipose tissue. These cells produce inflammatory substances themselves. Being overweight thereby leads to a low-grade chronic inflammation. If an infection with SARS-CoV-2 then occurs, there is a high risk of an overreaction of the immune system leading to hyperinflammation and cytokine storm. This represents a potentially life-threatening derailment of the immune system, which can further lead to paracrine injuries.