Effects of collagen peptide supplementation on cardiovascular markers: a systematic review and meta-analysis of randomised, placebo-controlled trials

Previous studies have advocated that collagen peptide supplementation (CPS) can positively affect cardiovascular health. However, the widespread impact of CPS on CVD-related markers is not fully resolved. Consequently, the current systematic review and meta-analysis aimed to assess the efficacy of CPS on CVD-related markers. A systematic search in the Scopus, PubMed and ISI Web of Science databases were completed to identify relevant randomised, placebo-controlled trials (RCT) published up to November 2021. Mean Differences were pooled using a random-effects model, while publication bias, sensitivity analyses and heterogeneity were assessed using previously validated methods. Twelve RCT, comprising of a total of eleven measured markers, were selected for the quantitative analysis. Pooled data revealed that CPS significantly decreased fat mass (-1 center dot 21 kg; 95 % CI: -2 center dot 13, -0 center dot 29; I-2 = 0 center dot 0 %; P = 0 center dot 010) and increased fat-free mass, based on body mass percentage (1 center dot 49 %; 95 % CI: 0 center dot 57, 2 center dot 42; I-2 = 0 center dot 0 %; P = 0 center dot 002). Moreover, collagen peptide supplementation led to a significant decrease in serum LDL (-4 center dot 09 mg/dl; 95 % CI: -8 center dot 13, -0 center dot 04; I-2 = 93 center dot 4 %; P = 0 center dot 048) and systolic blood pressure (SBP) (-5 center dot 04 mmHg; 95 % CI: -9 center dot 22, -0 center dot 85; I-2 = 98 center dot 9 %; P = 0 center dot 018). Our analysis also indicated that CPS did not affect glycemic markers. Our outcomes indicate that CPS reduces fat mass, LDL and SBP while increasing fat-free mass. Future investigations with longer CPS duration are needed to expand on our results.