European Journal of Nutrition

, Volume 54, Issue 7, pp 1151–1160 | Cite as

A low dietary intake of cod protein is sufficient to increase growth, improve serum and tissue fatty acid compositions, and lower serum postprandial glucose and fasting non-esterified fatty acid concentrations in obese Zucker fa/fa rats

  • Aslaug Drotningsvik
  • Svein Are Mjøs
  • Ingmar Høgøy
  • Tore Remman
  • Oddrun Anita Gudbrandsen
Original Contribution



Studies in rats suggest that fish proteins may improve lipid and glucose regulation and could thus be a potential tool in the treatment of obesity-related comorbidities. To date, all published rat studies on dietary fish protein have been designed with 50 or 100 % of dietary proteins from fish. As it is not common, nor advised, to consume fish as the only protein source in a healthy diet, mechanistic studies on the effects of diets with low dose fish proteins are needed. Here, we investigate whether a low dose of cod protein would affect glucose homeostasis and lipid metabolism in obese Zucker fa/fa rats.


Twelve male obese Zucker fa/fa rats consumed diets where cod proteins accounted for 25 % of the total protein intake with the remaining 75 % from casein (COD) or 100 % of protein as casein (CAS) for 4 weeks.


Rats fed COD achieved a higher body weight without affecting adiposity and thigh muscle mass after 4 weeks, but liver weight and hepatic cholesterol level were higher than in CAS-fed rats. Fasting serum level of non-esterified fatty acids and 2 h postprandial glucose level were lower in COD than in CAS. The fatty acid metabolism was beneficially affected by the COD diet, with e.g., higher ratio of n-3/n-6 PUFAs in serum, liver and adipose tissue when compared to CAS.


A low intake of cod protein (25 % of protein intake) was sufficient to beneficially affect lipid metabolism and postprandial glucose regulation in obese fa/fa rats.


Obesity Fish protein Insulin Tumor necrosis factor-alpha Inflammation 



The present research has been supported by funding from the Bergen Medical Research Foundation.

Conflict of interest

I.H. is a minor shareholder in Seagarden AS. The other authors declare no conflicts of interest.


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Copyright information

© Springer-Verlag Berlin Heidelberg 2014

Authors and Affiliations

  • Aslaug Drotningsvik
    • 1
  • Svein Are Mjøs
    • 2
    • 3
  • Ingmar Høgøy
    • 4
  • Tore Remman
    • 5
  • Oddrun Anita Gudbrandsen
    • 1
  1. 1.Department of Clinical MedicineUniversity of BergenBergenNorway
  2. 2.Department of ChemistryUniversity of BergenBergenNorway
  3. 3.Nofima BioLabFyllingsdalenNorway
  4. 4.Blue ProteinAustevollNorway
  5. 5.Nutrimar ASTrondheimNorway

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