Supplementation with Low Doses of a Cod Protein Hydrolysate on Glucose Regulation and Lipid Metabolism in Adults with Metabolic Syndrome: A Randomized, Double-Blind Study

Abstract

<jats:p>The risk of cardiovascular diseases and type 2 diabetes mellitus are increased in subjects with metabolic syndrome (MetS), and hydrolyzed fish protein may have favorable effects on metabolic health. Here, we investigated the effect of 8 weeks supplementation with 4 g of cod protein hydrolysate (CPH) on glucose metabolism, lipid profile and body composition in individuals with MetS in a double-blind, randomized intervention study with a parallel-group design. Subjects received a daily supplement of CPH (n = 15) or placebo (n = 15). Primary outcomes were serum fasting and postprandial glucose levels. Secondary outcomes were fasting and postprandial insulin and glucagon-like peptide 1 (GLP-1), fasting lipid concentrations and body composition. No difference was observed between CPH and placebo for insulin, glucose or GLP-1 after 8 weeks intervention. Fasting triacylglycerol decreased in both the CPH group and placebo group, with no change between groups. Fasting total cholesterol and low-density lipoprotein cholesterol decreased significantly within both groups from baseline to study end, but no difference was observed between the two groups. In conclusion, supplementing with a low dose of CPH in subjects with MetS for 8 weeks had no effect on fasting or postprandial levels of insulin, glucose or GLP-1, lipid profile or body composition.</jats:p>

A Narrative Review of the Anti‐Hyperglycemic and Satiating Effects of Fish Protein Hydrolysates and Their Bioactive Peptides

“…Nevertheless, there have been multiple studies recently published investigating the antidiabetic and satiating effect of a cod protein hydrolysate; however, there appears to be no significant effect on plasma hormones, blood glucose, or satiety with one study reporting a reduction in plasma insulin. [35,[89][90][91] Initially this appears to be due to a very low dosage regimen (a maximum of 4 g per day) but a separate study performed by Hovland et al showed an effect on glucose tolerance by a cod protein supplement through ingestion of 2.5 g per day for 8 weeks. [92] The important differentiation between these studies is likely that Hovland et al used an unhydrolyzed cod protein supplement, highlighting that the bioactivity of the protein is impacted by the hydrolysis process, and in this case hydrolysis may have negatively impacted the bioactivity.…”

“…Nevertheless, there have been multiple studies recently published investigating the anti‐diabetic and satiating effect of a cod protein hydrolysate; however, there appears to be no significant effect on plasma hormones, blood glucose, or satiety with one study reporting a reduction in plasma insulin. [ 35,89–91 ] Initially this appears to be due to a very low dosage regimen (a maximum of 4 g per day) but a separate study performed by Hovland et al. showed an effect on glucose tolerance by a cod protein supplement through ingestion of 2.5 g per day for 8 weeks.…”

The Effect of Supplementation with Low Doses of a Cod Protein Hydrolysate on Satiety Hormones and Inflammatory Biomarkers in Adults with Metabolic Syndrome: A Randomized, Double-Blind Study

“…Energy and protein intake from the supplement were added to the end of study dietary records (CPH group: 44 kcal, 4 g protein; placebo group: 46.5 kcal, 0 g protein). Details about the end of study energy intake is reported in a previous publication [30]. Calculations of energy and macronutrient intake were determined using "Kostholdsplanleggeren" (Norwegian Food Safety Authority, Norwegian Directorate of Health, Oslo) [34].…”

“…The level of significance was set to p < 0.05. A power calculation was not done in the original study due to lack of data to base it upon [30]. Therefore, no estimation of sample size of the current measurements was done prior to the study.…”

“…Limited data exists on long-term supplementation of cod protein in a population with metabolic abnormalities, yet it is an important abnormality to study. We have previously reported on the effects on fasting and postprandial glucose metabolism, as well as lipid metabolism and body composition in subjects with MetS after supplementation with 4 g of CPH for 8 weeks [30]. In the present study, we aimed to investigate if daily supplementation with the same low dose of CPH for 8 weeks would influence circulating levels of ghrelin, adiponectin, leptin, high-sensitivity CRP (hs-CRP) and a selection of other inflammatory markers.…”