Effects of Oats (Avena sativa L.) on Inflammation: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

Abstract

Background: Oat and its compounds have been found to have anti-inflammatory effects. Through this systematic review and meta-analysis, we aimed to determine an evidence-based link between oat consumption and inflammatory markers.Methods: The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines were followed. By the end of April 2021, we included randomized controlled trials (RCTs) that investigated the anti-inflammatory effect of oat and oat-related products through screening PubMed, Embase, Web of Science, ClinicalTrial.gov, and CENTRAL. Meta-analysis was conducted with a random-effect model on the standardized mean difference (SMD) of the change scores of inflammatory markers, including C-reactive protein (CRP), tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), and interleukin-8 (IL-8). Subgroup analyses were conducted to stratify confounding variables. The risk of bias was evaluated using the Cochrane risk of bias tool and Grading of Recommendations, Assessment, Development and Evaluation (GRADE) was applied to report the quality of evidence. This study was registered in the International Prospective Register of Systematic Reviews (PROSPERO; CRD42021245844).Results: Systematic screening of five databases yielded 4,119 studies, of which 23 RCTs were finally selected. For the four systemic inflammatory markers analyzed, no significant alterations were found after oat consumption. However, oat intake was found to significantly decrease CRP levels in subjects with one or more health complications (SMD: −0.18; 95% CI: −0.36, 0.00; P = 0.05; I2 = 10%). Furthermore, IL-6 levels were significantly decreased in subjects with dyslipidemia (SMD = −0.34; 95% CI: −0.59, −0.10; P = 0.006; I2 = 0%). These beneficial effects might be attributed to the effects of avenanthramide and β-glucan.Conclusions: Overall evidence supporting the alleviation of inflammatory response by oat intake was poor, calling for future studies including a larger sample size to confirm the findings.

Sprouting and Hydrolysis as Biotechnological Tools for Development of Nutraceutical Ingredients from Oat Grain and Hull

“…Moreover, FP and BP from OG and SO increased the levels of IL-10 ( p < 0.05)—an anti-inflammatory cytokine able to inhibit the synthesis of proinflammatory cytokines in macrophages. Our results agree with existing evidence supporting the anti-inflammatory properties of oats attributed mainly to avenanthramides and β-glucans [ 104 ].…”

The Multicomponent Medicinal Product Hepar Compositum Reduces Hepatic Inflammation and Fibrosis in a Streptozotocin- and High-Fat Diet-Induced Model of Metabolic Dysfunction-Associated Steatotic Liver Disease/Metabolic Dysfunction-Associated Steatohepatitis

“…Similarly, Taraxacum officinale (common dandelion) is considered to have antidiabetic properties [15] and has been reported to protect against chemically induced liver toxicity in rats [16]. Avena sativa (oat) has also been described to have antiinflammatory properties [17] and can protect against LPS-induced liver injury [18].…”

Efficacy of oats for dyslipidaemia: protocol for a systematic review and meta-analysis

“…Additionally, the target population is distinct, which may entail disparate results. 28 29 Numerous oat products, such as oatmeal, rolled oats, and oat bread, are readily available in real-world practical dietary plans. Thus, in this protocol, we propose to focus on various oat preparations and oat components and to conduct a systematic review and meta-analysis to compare the oat diet to other diets in patients with dyslipidaemia.…”

“…They did, however, examine the effects of oat on inflammatory factors or cardiovascular disease risk factors, rather than meta-analyses that specifically examined dyslipidaemias. Additionally, the target population is distinct, which may entail disparate results 28 29. Numerous oat products, such as oatmeal, rolled oats, and oat bread, are readily available in real-world practical dietary plans.…”