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

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. Disciplines Arts and Humanities | Life Sciences | Medicine and Health Sciences | Social and Behavioral Sciences Publication Details Murphy, K. J., Meyer, B. J., Mori, T. A., Burke, V., Mansour, J., Patch, C. S., Tapsell, L. C., Noakes, M., Clifton, P. A., Barden, A., Puddey, I. B., Beilin, L. J. & Howe, P. R C. (2007). Impact of foods enriched with omega-3 long chain polyunsaturated fatty acids on erythrocyte omega-3 levels and cardiovascular risk factors. The British Journal of Nutrition: an international journal of nutritional science, 97 (4), 749-757. Authors Karen J. Murphy, Barbara J. Meyer, Trevor A. Mori, Valerie Burke, Jackie Mansour, Craig S. Patch, L. C. Tapsell, Manny Noakes, Peter A. Clifton, Anne Barden, Ian B. Puddey, Lawrence J. Beilin, and Peter R. C. Howe This journal article is available at Research Online: http://ro.uow.edu.au/hbspapers/3274 Impact of foods enriched with n-3 long-chain polyunsaturated fatty acids on erythrocyte n-3 levels and cardiovascular risk factors Karen J. Murphy, Barbara J. Meyer, Trevor A. Mori, Valerie Burke, Jackie Mansour, Craig S. Patch, Linda C. Tapsell, Manny Noakes, Peter A. Clifton, Anne Barden, Ian B. Puddey, Lawrence J. Beilin and Peter R. C. Howe* Nutritional Physiology Research Centre, Division of Health Sciences, University of South Australia and School of Molecular & Biomedical Science, University of Adelaide, Adelaide, SA 5000 Smart Foods Centre, University of Wollongong, Wollongong, NSW 2522 Australia School of Medicine and Pharmacology, Royal Perth Hospital Unit, University of Western Australia, Perth, WA 6000 Australia Division of Health Sciences & Nutrition, CSIRO, Adelaide, SA 5000 Australia (Received 29 August 2006 – Revised 5 November 2006 – Accepted 16 November 2006) 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; .1·6mmol/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 þ 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 þ DHA intake from 0·2 to 1·0 g/d. However, the n-3 longchain 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. Functional foods: n-3 Long-chain polyunsaturated fatty acids: Processed foods: Dietary intervention: Cardiovascular disease The CVD health benefits of n-3 long-chain PUFA consumption have been demonstrated in experimental animal and human studies, resulting in approval by the US Food and Drug Administration of a qualified health claim for n-3 long-chain PUFA and coronary heart disease (USFDA, 2004). A high n-3 long-chain PUFA status is thought to be cardioprotective through reduction of risk factors such as dyslipidaemia, hypertension, thrombosis and arrhythmia (McLennan et al. 1996; Hu & Willet, 2002; Wijendran & Hayes, 2004) and improvement of arterial compliance, endothelial vasodilator function (Nestel et al. 2002) and heart rate variability (Christensen, 2003). In the GISSI-Prevenzione study, a large-scale intervention trial in post-myocardial infarction patients, supplementation with 850mg/d n-3 longchain PUFA reduced total mortality, cardiovascular mortality and, specifically, sudden cardiac death (GISSI-Prevenzione Investigators, 1999). To maintain cardiovascular health, the American Heart Association recommends eating at least two fatty-fish meals per week, equalling 400–500mg/d n-3 longchain PUFA. The International Society for the Study of Fatty Acids and Lipids recommends consuming at least 500mg/d of EPA and DHA, and the Australian National Health and Medical Research Council recommends consuming 410mg/d for women and 630mg/d for men (Baghurst, 2005). Countries with a high fish intake readily achieve this target, e.g. average n-3 long-chain PUFA consumption in Japan is 1·6 g/d (Dolecek, 1992). However, these recommendations may be difficult to attain in countries with traditionally low fish intake such as the USA and Australia, where median n-3 long-chain PUFA intakes are only 100 and 140mg/d, respectively (Meyer et al. 2003). An alternative strategy to increase the n-3 long-chain PUFA status of the population is to expand the range of foods containing n-3 long-chain PUFA. A variety of foods including *Corresponding author: Professor Peter Howe, fax: þ61-8-8302-2178, email [email protected] Abbreviations: BP, blood pressure; CRP, C-reactive protein; TBX2, thromboxane B2; TG, triacylglycerols; WHR, waist to hip ratio. British Journal of Nutrition (2007), 97, 749–757 DOI: 10.1017/S000711450747252X q The Authors 2007