Efficacy of supplementation with nutrients and dietary supplements on recovery and inflammatory response among patients with COVID-19: a network meta-analysis.

Background: At present, the clinical course of COVID-19 is synergistically influenced by the systemic inflammatory storm and nutritional deterioration triggered by COVID-19. Nutrition interventions have demonstrated potential clinical value. Objective: This study aims to systematically compare the relative efficacy of different dietary patterns and nutritional supplements on key outcomes among adult patients with COVID-19, and to identify the optimal regimen of nutrition intervention. Methods: PubMed, Embase, Cochrane Library, and Web of Science, were systematically searched. Randomized controlled trials (RCTs) were independently screened. The risk of bias was assessed using the Cochrane Risk of Bias 2.0 (RoB 2.0) tool. The inflammation status of patients was measured by alterations in indicators such as interleukin-6 (IL-6) and neutrophil-to-lymphocyte ratio (NLR), while recovery was evaluated based on changes in the number of patients with adverse complications, including cough and death. Statistical analysis was performed in R (version 4.5.1). A random-effects model under the Bayesian framework was adopted to pool mean differences (MDs) or risk ratios (RRs) alongside their corresponding 95% credible intervals (CrIs). Additionally, regression analyses were performed for sample size, treatment duration, and disease severity of patients. The confidence in the evidence was assessed using the Confidence in Network Meta-Analysis (CINeMA). Results: The efficacy of interventions varied for different immune and clinical outcomes among patients with COVID-19. Compared with standard of care (SoC) alone, vitamin C + SoC significantly decreased IL-6(vitamin C + SoC vs. SoC alone: MD = -88.77, 95% CrI: -139.02, -38.66, CINeMA: low certainty). Compared with SoC, COVID-19 patients supplemented with nanocurcumin+SoC showed a significant increase in lymphocyte count (nanocurcumin + SoC vs. SoC: MD = 4.76, 95% CrI: 2.91, 6.62, CINeMA: NA). In comparison with SoC, COVID-19 patients supplemented with pomegranate juice exhibited a marked increase in NLR (pomegranate juice + SoC vs. Placebo: MD = 1.04, 95% CrI: 0.21, 1.88, CINeMA: very low certainty). Conclusion: Compared with SoC alone, significant changes were observed in IL-6, NLR, and lymphocyte count among patients suffering from COVID-19 following supplementation with nutrients and dietary supplements. Systematic review registration: PROSPERO (CRD420251110943).