, Volume 36, Issue 1, pp 7–13

A long-term seal- and cod-liver-oil supplementation in hypercholesterolemic subjects

  • Jan Brox
  • Kirsten Olaussen
  • Bjarne Østerud
  • Edel O. Elvevoll
  • Eivin Bjørnstad
  • Tormod Brenn
  • Guttorm Brattebø
  • Hanne Iversen


In this long-term study, we wanted to explore the effect of dietary supplementation of seal oil (SO) as compared cod-liver oil (CLO) on subjects with moderate hypercholesterolemia. The test parameters included fatty acid composition in serum, blood lipids, platelet aggregation, and the activity of blood monocytes. After a run-in period of 6 mon, 120 clinically healthy hypercholesterolemic (7.0–9.5 mmol/L; 270–366 mg/dL) subjects were randomly selected to consume either 15 mL of SO or CLO daily for 14 mon followed by a 4-mon wash-out period. A third group was not given any dietary supplement (control). Consumption of marine oils (SO and CLO) changed the fatty acid composition of serum significantly. Maximal levels were achieved after 10 mon. No further changes were seen after 14 mon. A wash-out period of 4 mon hardly altered the level of n−3 fatty acids in serum. Addition of SO gave 30% higher level of eicosapentaenoic acid, as compared to CLO. Subjects taking SO or CLO had lower whole-blood platelet aggregation than the control group. Neither SO nor CLO had any effects on the levels of serum total cholesterol, high-density lipoprotein cholesterol, postprandial triacylglycerol, apolipoproteins A1 and B100, lipoprotein (a), monocyte function expressed as monocyte-derived tissue factor expression, and tumor necrosis factor.



alanine amino transferase


alkaline phosphatase




aspartate aminotransferase


codliver oil


C reactive protein


coefficient of variation


docosahexaenoic acid


eicosapentaenoic acid


high density lipoprotein


lipoprotein (a)


monounsaturated fatty acids


polyunsaturated fatty acids


saturated fatty acids


seal oil


ussue factor


tumor necrosis factor


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Copyright information

© AOCS Press 2001

Authors and Affiliations

  • Jan Brox
    • 1
  • Kirsten Olaussen
    • 2
  • Bjarne Østerud
    • 3
  • Edel O. Elvevoll
    • 4
  • Eivin Bjørnstad
    • 5
  • Tormod Brenn
    • 6
  • Guttorm Brattebø
    • 7
  • Hanne Iversen
    • 2
  1. 1.Department of Clinical ChemistryUniversity Hospital of TromsøTromsøNorway
  2. 2.Hammerfest HospitalHammerfestNorway
  3. 3.Department of Biochemistry, Institute of Medical BiologyUniversity of TromsøTromsøNorway
  4. 4.Norwegian Institute of Fisheries and Aquaqulture Ltd.TromsøNorway
  5. 5.University College of FinnmarkAltaNorway
  6. 6.Institute of Community MedicineUniversity of TromsøTromsøNorway
  7. 7.University Hospital of BergenBergenNorway

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