Mediterranean diet and the risk of COVID-19 in the ‘Seguimiento Universidad de Navarra’ cohort

Perez-Araluce, R.; Martinez-Gonzalez, M.A.; Fernández-Lázaro, C.I.; Bes-Rastrollo, M.; Gea, A.; Carlos, S.

BACKGROUND & AIMS: A potential protection against COVID-19 infection by a high-quality dietary pattern is to be expected given the biological plausibility supporting the beneficial effects of adequate nutrition on the immune system. However, knowledge on the relationship between long-term maintained healthy dietary patterns, such as the Mediterranean diet, and the risk of SARS-2-Cov infection is still sparse. We longitudinally assessed this association in a well-known Mediterranean cohort. METHODS: We assessed 9677 participants from the SUN Project, a prospective cohort of middle-aged university graduates in Spain. We inquired about a positive result in a COVID-19 diagnostic test during the months of February to December 2020. After excluding health professionals (HP), 5194 participants were included in the statistical analyses (mean age: 52.6, SD: 12.4; 55.2% women). Food habits were assessed at baseline using a previously validated semiquantitative 136-item food frequency questionnaire. Adherence to the Mediterranean diet (cumulative average of 2 repeated measurements separated 10 years apart) was assessed using the 0-to-9 Mediterranean Diet Score (MDS). We used multivariable logistic regression models to estimate odds ratios and 95% confidence intervals for incident COVID-19 according to the MDS. RESULTS: Among 5194 non-HP participants, 122 reported to have received a diagnosis of COVID-19 based on a specific diagnostic test. Participants with intermediate adherence to the Mediterranean diet (MDS ≥4 & <7) had a significantly lower odds of developing COVID-19 (multivariable-adjusted OR = 0.50, 95% CI, 0.34–0.73), and those with the highest adherence (MDS ≥ 7) exhibited the lowest risk (multivariable-adjusted OR = 0.36, 0.16–0.84, p for trend < 0.001) as compared with participants with MDS ≤3. This inverse association remained robust within subgroups and in sensitivity analyses. Notwithstanding, no significant associations were observed for health professionals (p for interaction = 0.06). CONCLUSION: In conclusion, better adherence to the Mediterranean diet may be associated with a lower risk of COVID-19. Our results are applicable only to persons who are not health professionals.