Green Tea Catechins and COVID-19: Epidemiological Trends and Therapeutic Perspectives.

Introduction: Pharmacological studies in vitro demonstrate the preventive and therapeutic potential of green tea and its constituent epigallocatechin-3-gallate (EGCG) in the fight against coronavirus disease 2019 (COVID-19). Previously reported correlations between per capita green tea consumption and COVID-19 morbidity/mortality suggest similar effects in vivo. Considering that some recent SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2) sub-variants are less influenced by EGCG, this study aimed to determine whether this affects the aforementioned correlations, focusing on comparisons between the periods before (2021) and after (2022-2024) the emergence of the Omicron variant.

Methods: Correlations between per capita green tea consumption and COVID-19 morbidity/mortality were calculated using multiple regression models accounting for several confounding factors in a subset (n=84) of countries/territories worldwide with Human Development Index (HDI) above 0.55.

Results: Higher per capita green tea consumption was associated with lower COVID-19 morbidity and mortality. Statistically significant correlations were observed in 2021-2024. Compared with 2021, the strength of both correlations decreased; the relative decrease in the strength of the correlation between per capita green tea consumption and COVID-19 mortality was notably less pronounced.

Discussion: This differential decrease at the epidemiological level supports the idea that green tea consumption may have not only preventive but also therapeutic value regarding COVID-19. This aligns with in vitro pharmacological evidence indicating that green tea constituents target distinct molecular pathways responsible for the entry of the virus and its replication.

Conclusion: While promising, these findings require further assessment in observational and interventional studies focused on potential therapeutic benefits.