Positive Health Online

Abstract

MURPHY and co-authors, Nutritional Physiology Research Centre, Division of Health Sciences, University of South Australia and School of Molecular & Biomedical Science, University of Adelaide, Adelaide, SA, Australia, have measured the impact of n-3 fatty acid supplementation on red blood cell lipids and the risk of cardiovascular disease.

Background

Consumption of fish or fish oils rich in the n-3 fatty acids EPA (eicosapentaenoic acid) and DHA (docosahexaenoic acid) may improve multiple risk factors for cardiovascular disease. The aim of this study was to determine whether regular consumption of foods enriched with n-3 fatty acids can improve n-3 fatty acid status (as measured in red blood cells) and cardiovascular health.

Methodology

Overweight volunteers with high levels of triacylglycerols were enrolled in a 6-month dietary intervention trial, and randomized to consume control foods or n-3-enriched foods to achieve an EPA + DHA intake of 1 gram per day. Test foods were substituted for equivalent foods in their regular diet. Red blood cell fatty acids, plasma triglycerides and other cardiovascular risk factors were monitored at 0, 3 and 6 months.

Results

There were no significant differences between groups for blood pressure, arterial compliance, glucose, insulin, lipids, C-reactive protein or urinary 11-dehydro-thromboxane B2 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 fatty acid content of red blood cells 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.

Conclusion

Sustainable increases in dietary intakes and erythrocyte levels of n-3 fatty acids can be achieved through regular consumption of suitably enriched processed foods. Such increases may be associated with reduced cardiovascular disease risk.

References

Murphy KJ et al. Impact of foods enriched with n-3 long-chain polyunsaturated fatty acids on erythrocyte n-3 levels and cardiovascular risk factors.  British Journal of Nutrition 97 (4): 749-757, Apr 2007.