Impact of foods enriched with n-3 long-chain polyunsaturated fatty acids on erythrocyte n-3 levels and cardiovascular risk factors

Karen J. Murphya1, Barbara J. Meyera2, Trevor A. Moria3, Valerie Burkea3, Jackie Mansoura3, Craig S. Patcha2, Linda C. Tapsella2, Manny Noakesa4, Peter A. Cliftona4, Anne Bardena3, Ian B. Puddeya3, Lawrence J. Beilina3 and Peter R. C. Howea1 

a1 Nutritional Physiology Research Centre, Division of Health Sciences, University of South Australia and School of Molecular & Biomedical Science, University of Adelaide, Adelaide, SA 5000

a2 Smart Foods Centre, University of Wollongong, Wollongong, NSW 2522 Australia

a3 School of Medicine and Pharmacology, Royal Perth Hospital Unit, University of Western Australia, Perth, WA 6000 Australia

a4 Division of Health Sciences & Nutrition, CSIRO, Adelaide, SA 5000 Australia


Consumption of fish or fish oils rich in the n-3 long chain PUFA EPA and DHA may improve multiple risk factors for CVD. The objective of this study was to determine whether regular consumption of foods enriched with n-3 long-chain PUFA can improve n-3 long-chain PUFA status (erythrocytes) and cardiovascular health. Overweight volunteers with high levels of triacylglycerols (TG; >1·6 mmol/l) were enrolled in a 6-month dietary intervention trial conducted in Adelaide (n 47) and Perth (n 39), and randomised to consume control foods or n-3-enriched foods to achieve an EPA + DHA intake of 1 g/d. Test foods were substituted for equivalent foods in their regular diet. Erythrocyte fatty acids, plasma TG and other CVD risk factors were monitored at 0, 3 and 6 months. There were no significant differences between groups for blood pressure, arterial compliance, glucose, insulin, lipids, C-reactive protein (CRP) or urinary 11-dehydro-thromboxane B2 (TXB2) over 6 months, even though regular consumption of n-3-enriched foods increased EPA + DHA intake from 0·2 to 1·0 g/d. However, the n-3 long-chain PUFA content of erythrocytes increased by 35 and 53 % at 3 and 6 months, respectively, in subjects consuming the n-3-enriched foods. These increases were positively associated with measures of arterial compliance and negatively associated with serum CRP and urinary 11-dehydro-TXB2 excretion. Sustainable increases in dietary intakes and erythrocyte levels of n-3 long-chain PUFA can be achieved through regular consumption of suitably enriched processed foods. Such increases may be associated with reduced CV risk.

(Received August 29 2006)

(Revised November 05 2006)

(Accepted November 16 2006)

Key Words:

  • Functional foods;
  • n-3 Long-chain polyunsaturated fatty acids;
  • Processed foods;
  • Dietary intervention;
  • Cardiovascular disease


c1 Corresponding author: Professor Peter Howe, fax: +61-8-8302-2178, email


  Abbreviations: BP, blood pressure; CRP, C-reactive protein; TBX2, thromboxane B2; TG, triacylglycerols; WHR, waist to hip ratio