Title: Diet quality and risk and severity of COVID-19: a prospective cohort study.

Authors: Merino, Jordi; Joshi, Amit D; Nguyen, Long H; Leeming, Emily R; Mazidi, Mohsen; Drew, David A; Gibson, Rachel; Graham, Mark S; Lo, Chun-Han; Capdevila, Joan; Murray, Benjamin; Hu, Christina; Selvachandran, Somesh; Hammers, Alexander; Bhupathiraju, Shilpa N; Sharma, Shreela V; Sudre, Carole; Astley, Christina M; Chavarro, Jorge E; Kwon, Sohee; Ma, Wenjie; Menni, Cristina; Willett, Walter C; Ourselin, Sebastien; Steves, Claire J; Wolf, Jonathan; Franks, Paul W; Spector, Timothy D; Berry, Sarah; Chan, Andrew T

Published In Gut, (2021 Nov)

Abstract: OBJECTIVE: Poor metabolic health and unhealthy lifestyle factors have been associated with risk and severity of COVID-19, but data for diet are lacking. We aimed to investigate the association of diet quality with risk and severity of COVID-19 and its interaction with socioeconomic deprivation. DESIGN: We used data from 592 571 participants of the smartphone-based COVID-19 Symptom Study. Diet information was collected for the prepandemic period using a short food frequency questionnaire, and diet quality was assessed using a healthful Plant-Based Diet Score, which emphasises healthy plant foods such as fruits or vegetables. Multivariable Cox models were fitted to calculate HRs and 95% CIs for COVID-19 risk and severity defined using a validated symptom-based algorithm or hospitalisation with oxygen support, respectively. RESULTS: Over 3 886 274 person-months of follow-up, 31 815 COVID-19 cases were documented. Compared with individuals in the lowest quartile of the diet score, high diet quality was associated with lower risk of COVID-19 (HR 0.91; 95% CI 0.88 to 0.94) and severe COVID-19 (HR 0.59; 95% CI 0.47 to 0.74). The joint association of low diet quality and increased deprivation on COVID-19 risk was higher than the sum of the risk associated with each factor alone (Pinteraction=0.005). The corresponding absolute excess rate per 10 000 person/months for lowest vs highest quartile of diet score was 22.5 (95% CI 18.8 to 26.3) among persons living in areas with low deprivation and 40.8 (95% CI 31.7 to 49.8) among persons living in areas with high deprivation. CONCLUSIONS: A diet characterised by healthy plant-based foods was associated with lower risk and severity of COVID-19. This association may be particularly evident among individuals living in areas with higher socioeconomic deprivation.

PubMed ID: 34489306

MeSH Terms: Adolescent; Adult; Aged; COVID-19/epidemiology; COVID-19/etiology*; COVID-19/prevention & control; Diet Surveys; Diet, Healthy; Diet/adverse effects*; Female; Humans; Male; Middle Aged; Prospective Studies; Risk Factors; Severity of Illness Index; Socioeconomic Factors; Surveys and Questionnaires; Young Adult