Effect of a cod protein hydrolysate on postprandial glucose metabolism in healthy subjects: a double-blind cross-over trial

• Published in: Journal of Nutritional Science
• Main Authors: Hanna Fjeldheim Dale, Caroline Jensen, Trygve Hausken, Einar Lied, Jan Gunnar Hatlebakk, Ingeborg Brønstad, Dag Arne Lihaug Hoff, Gülen Arslan Lied
• Format: Article in Journal/Newspaper
• Language: English
• Published: Cambridge University Press 2018
• Subjects: Marine protein hydrolysate; Fish protein; Marine peptides; Glucose metabolism; Nutrition. Foods and food supply; TX341-641; Medicine; R; atlantic cod; Gadus morhua
• Online Access: https://doi.org/10.1017/jns.2018.23; https://doaj.org/article/ed930ca987ce421184b66fd422454125

The increased prevalence of lifestyle diseases, such as the metabolic syndrome and type 2 diabetes mellitus (T2DM), calls for more knowledge on dietary treatments targeting the specific metabolic pathways involved in these conditions. Several studies have shown a protein preload before a meal to be effective in lowering the postprandial glycaemic response in healthy individuals and patients with T2DM. The aim of the present study was to assess the effect of a marine protein hydrolysate (MPH) from Atlantic cod (Gadus morhua) on postprandial glucose metabolism in healthy, middle-aged to elderly subjects. This double-blind cross-over trial (n 41) included two study days with 4–7 d wash-out in between. The intervention consisted of 20 mg of MPH (or casein as control) per kg body weight given before a breakfast meal. The primary outcome was postprandial response in glucose metabolism, measured by samples of serum glucose, insulin and plasma glucagon-like peptide 1 (GLP-1) in 20 min intervals for 180 min. In a mixed-model regression analysis, no differences were observed between MPH and control for postprandial glucose concentration (mean difference: −0·04 (95 % CI –0·17, 0·09) mmol/l; P = 0·573) or GLP-1 concentration (mean difference between geometric means: 1·02 (95 % CI 0·99, 1·06) pmol/l; P = 0·250). The postprandial insulin concentration was significantly lower after MPH compared with control (mean difference between geometric means: 1·067 (95 % CI 1·01, 1·13) mIU/l; P = 0·032). Our findings demonstrate that a single dose of MPH before a breakfast meal reduces postprandial insulin secretion, without affecting blood glucose response or GLP-1 levels, in healthy individuals. Further studies with repeated dosing and in target groups with abnormal glucose control are warranted.