Westernized food and fermented vegetables.
Westernized diets contain a reduced amount of fermented vegetables5,62 and may be prone to increasing insulin resistance and thereby severe COVID-19. The transcription factor Nrf2 may be at the centre of the regulatory pathways (Figure 3).
COVID-19 and food fermentation .
Although nutritional epidemiology has been criticized on several fronts - its inability to measure diet accurately and its reliance on observational studies to address etiologic questions63 - there seems to be sufficient evidence to raise several conclusions (to be tested appropriately).
Many factors may play a role in the extension and severity of COVID-19. Diet may represent only one of the possible causes of COVID-19 severity (Table 1). The effects of the microbiome 64 and diet6 on SARS-CoV-2 infection suggest that their role in the gut could be a target for COVID-19 interventions. It is proposed that countries with a large consumption of traditional LAB-fermented vegetables are those showing lower COVID-19 death rates. This hypothesis should be confirmed by experimental studies (Box 1). If certain foods are found to be associated with a prevention of COVID-19 prevalence or severity, it may be of interest to study their LAB composition in order to eventually find some common mechanisms and targets for therapy.
Jean Bousquet, MD, Charité, Universitätsmedizin Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Comprehensive Allergy Center, Department of Dermatology and MACVIA-France, Montpellier, France Allergy, Berlin, Germany
Josep M Anto, MD, ISGlobAL, Centre for Research in Environmental Epidemiology (CREAL), IMIM (Hospital del Mar Research Institute), Universitat Pompeu Fabra (UPF), CIBER Epidemiología y Salud Pública (CIBERESP), Barcelona, Spain
Wienczyslawa Czarlewski, MD, Medical Consulting Czarlewski, Levallois, and MASK-air, Montpellier France.
Tari Haahtela, MD, Skin and Allergy Hospital, Helsinki University Hospital, Helsinki, Finland.
Susana C Fonseca, PhD, GreenUPorto - Sustainable Agrifood Production Research Centre, DGAOT, Faculty of Sciences, University of Porto, Campus de Vairão, Rua da Agrária, Porto, Portuga
Guido Iaccarino, MD, Federico II University, Department of Advanced Biomedical Sciences, Napoli, Italy.
Hubert Blain, MD, Pole Gérontologie, University Hospital, Montpellier University, MUSE, Montpellier.
Cezmi A Akdis, MD, Swiss Institute of Allergy and Asthma Research (SIAF), University of Zurich, Davos, Switzerland
Torsten Zuberbier, MD, Charité, Universitätsmedizin Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Comprehensive Allergy Center, Department of Dermatology, Berlin Germany
JB designed the concept. All the other authors reviewed the concept and approved the paper