Green Tea Catechins Against COVID-19: Lower COVID-19 Morbidity and Mortality in Countries with Higher per capita Green Tea Consumption

Abstract

Background: Several vaccines are currently validated for COVID-19 prevention and mass vaccination has already been started in many countries. Nevertheless, it is likely that the development of an efficient therapy that reduces COVID-19 severity/mortality would be still important for a rather prolonged time, in particular, due to new variants of SARS-CoV-2. Several lines of emerging evidence suggest that green tea catechins such as epigallocatechin-3-gallate have direct anti-viral activity and affect factors associated with COVID-19 severity. Objective: Considering that green tea catechins are major constituents of green tea, it may be expected that countries with higher per capita green tea consumption would be less affected by COVID-19. This study assessed this possibility. Methods: Among countries with a population of at least 3 million (n=134), those with relatively high (above 150 g) per capita green tea consumption have been identified (n=21); (ii) normalized to population values of COVID-19 cases (morbidity) and deaths (mortality) for groups of countries with high and low per capita green tea consumption were compared. Results: Striking differences in COVID-19 morbidity and mortality between groups of countries with ‘high’ and ‘low’ green tea consumption were found. The differences were still observed after the adjustment for the onset of the disease. An analysis using the multiple linear regression approach suggests that the associations are present at the level of individual countries. Conclusions: Results of this study, taken together with emerging pharmacological evidence, suggest that green tea catechins can give valuable clues for the treatment/amelioration of COVID-19.