COVID-19 and obesity: fighting two pandemics with intermittent fasting

Obesity is strongly and independently associated with an increased risk of se-vere illness and death from coronavirus disease 2019 (COVID-19). The patho-physiological changes that result from elevated body weight lead to metabolic dysfunction, chronic inflammation, impaired immunological responses, and mul-tisystem disorders, which increase vulnerability to severe illness from COVID-19. While vaccination strategies are under way across the world, the second and third waves of the pandemic, along with the emergence of novel severe acute re-spiratory syndrome coronavirus 2 (SARS-CoV-2) strains, continue to threaten the stability of medical systems worldwide. Furthermore, evidence from previous pandemics suggests that vaccines are less effective in obese individuals than in their healthy-weight counterparts over the long term. Therefore, a consider-ation of lifestyle changes that can boost metabolic health and immunity is critical to reduce the risk of complications and severe illness from viral infection. In this review, we discuss the potential mechanisms linking excess body weight with COVID-19 morbidity. We also present evidence that intermittent fasting (IF), a dietary program that has gained popularity in recent years, may be an effective strategy to improve metabolic health and immunity and thus reduce the impact of obesity on COVID-19 morbidity and mortality.