The Association between Dietary Inflammatory Index with Risk of Coronavirus Infection and Severity: A Case-Control Study

Background: Recently, several have evaluated the association between the components of the dietary inflammatory index (DII) score with the risk and severity of Coronavirus Disease 2019 (COVID-19). For the first time, we examined the association between DII ® with risk of coronavirus infection and symptom severity through a case-control study in Iran. Methods: The present case-control study was conducted on COVID-19 cases (n = 100) and healthy control (n = 100) volunteer, aged from 18 to 65 years. Dietary intake, DII, body mass index, COVID-19 infection, and the severity of its symptoms were assessed for each participant. A multivariable logistic regression analysis test was used to estimate the odds ratio and 95% confidence interval. Results: Our results demonstrated that COVID-19–infected patients were significantly older and had longer history of diabetes as compared to the healthy control group ( P <.05). Furthermore, the participants with COVID-19 had a significantly greater intake of total fat ( P =0.259), saturated fat ( P =0.005), and dietary fiber ( P = .004). In contrast, individuals in the healthy control group had a higher intake of carbohydrate ( P = .005), sodium ( P <.001), and iron ( P <.001). However, there was no significant difference in DII score between COVID-19 and healthy controls ( P =.259). In addition, we did not detect any specific association between DII score and risk of COVID-19 infection (odds ratio = 1.08, 95% confidence interval: 0.92 to 1.27; P =.294) and the severity of its symptoms ( P >.05). Conclusions: There appears to be no specific association between DII score and risk of COVID-19 infection and the severity of its symptoms. More prospective cohort studies are necessary to confirm the veracity of our results.