L-肉碱补充可能有益于改善炎症状况并降低炎症细胞因子水平。因此，根据随机对照试验（RCT）的发现，该系统评价和荟萃分析旨在研究L-肉碱补充对成年人炎症的影响。为了获取截至2022年10月的可接受文章，我们在PubMed、ISI Web of Science、Cochrane图书馆和Scopus等数据库中进行了详尽的搜索。采用随机效应模型估计加权均数差（WMD）。我们在本研究中纳入了48个RCT（n=3255），共51个效应大小。与安慰剂组相比，L-肉碱补充对C-反应蛋白（CRP）（p<0.001）、白细胞介素-6（IL-6）（p=0.001）、肿瘤坏死因子-α（TNF-α）（p=0.002）、丙二醛（MDA）（p=0.001）、总抗氧化能力（TAC）（p=0.029）、丙氨酸转氨酶（ALT）（p<0.001）和天冬氨酸转氨酶（AST）（p<0.001）具有显著效应。亚组分析显示，在试验持续时间≥12周的2型糖尿病和BMI≥25 kg/m2患者中，L-肉碱补充对CRP和TNF-α有降低作用。L-肉碱补充在任何试验剂量和试验持续时间≥12周的超重和正常BMI受试者中降低了ALT水平，并在超重受试者和试验剂量≥2 g/天时降低了AST水平。该荟萃分析揭示了L-肉碱补充通过提高TAC水平和降低血清中的CRP、IL-6、TNF-α和MDA水平，有效减少了炎症状态。©2023版权所有。作者（们）享有Springer Nature Switzerland AG的独家许可。

L-carnitine supplementation may be beneficial in improving inflammatory conditions and reducing the level of inflammatory cytokines. Therefore, according to the finding of randomized controlled trials (RCTs), the systematic review and meta-analysis aimed to investigate the effect of L-carnitine supplementation on inflammation in adults. To obtain acceptable articles up to October 2022, a thorough search was conducted in databases including PubMed, ISI Web of Science, the Cochrane Library, and Scopus. A random-effects model was used to estimate the weighted mean difference (WMD). We included the 48 RCTs (n = 3255) with 51 effect sizes in this study. L-carnitine supplementation had a significant effect on C-reactive protein (CRP) (p < 0.001), interleukin-6 (IL-6) (p = 0.001), tumor necrosis factor-α (TNF-α) (p = 0.002), malondialdehyde (MDA) (p = 0.001), total antioxidant capacity (TAC) (p = 0.029), alanine transaminase (ALT) (p < 0.001), and aspartate transaminase (AST) (p < 0.001) in intervention, compared to the placebo group. Subgroup analyses showed that L-carnitine supplementation had a lowering effect on CRP and TNF-α in trial duration ≥ 12 weeks in type 2 diabetes and BMI ≥ 25 kg/m2. L-carnitine supplementation reduced ALT levels in overweight and normal BMI subjects at any trial dose and trial duration ≥ 12 weeks and reduced AST levels in overweight subjects and trial dose ≥ 2 g/day. This meta-analysis revealed that L-carnitine supplementation effectively reduces the inflammatory state by increasing the level of TAC and decreasing the levels of CRP, IL-6, TNF-α and MDA in the serum.© 2023. The Author(s), under exclusive licence to Springer Nature Switzerland AG.