Diet quality and risk of SARS-CoV-2 infection or COVID-19 disease: a systematic review

Abstract

Abstract Background The COVID-19 disease pandemic highlighted the importance of healthy diets in the management of SARS-CoV-2 infection and COVID-19 disease. Evidence suggests the influence of the diet and dietary patterns during post-COVID-19 disease, and the impact of the COVID-19 disease pandemic on dietary habits and quality. However, limited evidence exists on the association between a healthy diet, and risk of SARS-CoV-2 infection and COVID-19 disease. Methods 5072 research articles from Scopus, EMBASE, PubMed and MEDLINE databases were identified for eligibility. Only studies that had prospective and cross-sectional study designs were included. Eight studies were extracted and were included in the current systematic review that explored Mediterranean diet and dietary components as dietary exposures, and SARS-CoV2 infection and COVID-19 disease as study outcomes. Results Amongst cross-sectional studies, a higher adherence to Mediterranean diet lowered the odds of COVID-19 disease between 12% (OR: 0.88; 95% CI: 0.81-0.97) and 84% (OR: 0.16; 95% CI: 0.08-0.32). Amongst prospective studies, a higher diet quality and adherence to a Mediterranean diet was associated with lower hazard ratio of 9% (HR: 0.91; 95% CI: 0.88-0.94), and the odds of COVID-19 diseases by 36% (OR: 0.64, 95% CI: 0.42-0.98) to 50% (OR: 0.50, 95% CI: 0.34-0.73), respectively. Conclusions Overall findings of the studies in this review support the concept that Mediterranean diet and other nutritious diets might lower the risk of COVID-19 disease. Awareness could be created by promoting nutrition education programmes. Finally, this review highlights the limited evidence, and requirement of further studies to explore the longitudinal associations between diet, and SARS-CoV2 infection and COVID-19 disease in order to make the findings more generalisable. Key messages • A nutritious diet is associated with lower risk of COVID-19 disease. • Longitudinal studies and nutritional awareness is required to promote the importance of diet quality to cautiously prevent the risk of SARS-CoV2 infection and COVID-19 disease.