Kimchi and Asian fermented foods as candidates for the partial control of severe COVID-19
Mainstream COVID-19 control strategies including social distancing, confinement and intensive case finding, testing, tracing and isolating are so far not enough to provide a SARS-CoV-2-free environment and restore a safe social life. There are hopes for a safe and effective vaccine, but this is unlikely to become available. So, there is a need to explore other potentially useful strategies. An area that has not been sufficiently considered is diet, both as a preventive and/or therapeutically useful intervention, encouraging people to eat more traditional foods containing fermented vegetables. We have suggested that fermented vegetables could be associated with a lower COVID-19 mortality due to their potent antioxidant effect among which sulforaphane and LABs are important. However, many other foods may have a similar activity. It should be noted that dietary supplements that over-activate Nrf2 may have side-effects.67
Robust evidence from observational studies would be helpful to formally investigate associations between fermented foods and clinical outcomes in COVID-19. State-of-the-art methods, including the use of DAGs (Directed Acyclic Graphs), may be needed to help assess whether the associations seen are likely to represent causal relationship68. A faster approach would be to develop large clinical trials in the appropriate populations. Interventions based on diets with a high intake of fermented foods like Kimchi or other fermented foods are unlikely to present ethical difficulties. Furthermore, the fact that a precise mechanism has been proposed would facilitate adding reliable biomarkers to the relevant clinical outcomes. Moreover, new drugs based on the components of these fermented foods may be of interest.
Corresponding author :
Professor Jean Bousquet
CHU Arnaud de Villeneuve, 371 Avenue du Doyen Gaston Giraud, 34295 Montpellier Cedex 5, France Tel +33 611 42 88 47, Fax +33 467 41 67 01