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

Mohammad Tavassoli, Gholamreza Askari, Vahid Hadi, Morad Esmaeil Zali, Cain C. T. Clark, Dr. Sayid Mahdi Mirghazanfari, Saeid Hadi


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.


Coronavirus; COVID‑19; dietary inflammatory index; symptoms

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