A Practical approach to increasing intakes of n-3 polyunsaturated fatty acids: use of novel foods enriched with n-3 fats.
A Practical approach to increasing intakes of n-3 polyunsaturated fatty acids: use of novel foods enriched with n-3 fats.
Year: 2003
Authors: R Metcalf, M James, E Mantzioris, I Cleland.
Publication Name: European Journal of Clinical Nutrition.
Publication Details: Volume 57; Page 1605.
Abstract:
A considerable body of evidence has demonstrated that the regular consumption of omega-3 (n-3) polyunsaturated fatty acids (PUFA) including eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) from marine sources, and alpha-linolenic acid (ALA) from plant oils such as flaxseed, is associated with significant beneficial effects on cardiovascular disease. As such, increased consumption of n-3 fatty acids has been recommended by a number of health authorities worldwide. Despite this, consumption of n-3 fatty acids in Western societies remains low, and increasing consumption to recommended levels would involve major alterations to dietary habits. An alternative strategy for a long-term increase in n-3 PUFA consumption is to provide a wide range of commercial food products and ingredients fortified with fish oil or ALA that are easily incorporated into the diet. In this study, a number of novel foods fortified with fish oil, and products high in ALA, were fed to humans to examine intakes of individual n-3 PUFA, dietary preferences, and the effect of different n-3 PUFA intakes on plasma and cellular fatty acids. Sixteen healthy males participated in this 6-week intervention study. Participants had a mean age of 39.2 +/- 4.4 y, and a mean body mass index (BMI) of 25.8 +/- 2.6 kg/m2. Subjects were provided with a range of food products high in n-3 fatty acids designed to increase their intake of n-3 PUFA, and decrease their intake of n-6 PUFA. Products high in ALA were enriched with canola oil and flaxseed. Foods high in EPA and DHA included fresh fish, canned fish, and a number of items fortified with fish oil including sausages, luncheon meat, and milk. Olive oil based salad dressing and mayonnaise, as well as muffins prepared with canola oil were also provided. Subjects were not instructed to consume set quantities of each food, but were to incorporate these foods into their normal diet in desired quantities. All participants completed weighted food records for 3 days/wk for 2 weeks prior to dietary intervention to provide baseline fatty acid intakes. Dietary records were also completed for the 4-week dietary intervention period. Fasting peripheral blood was sampled at -2, 0, 2, and 4 weeks for analysis of plasma, platelet, and mononuclear cell phospholipid fatty acids. A small but significant increase in BMI was reported during the first 2-week dietary invention period, followed by a non-significant increase at the end of the 4-weeks. There were significant increases in intakes of oleic acid, ALA, EPA, and DHA, as well as a significant decrease in LA intake during the intervention period in comparison to baseline. ALA increased from 1.4 to 4.1g/day, EPA from 0.03 to 0.51g/day, and DHA from 0.09 to 1.01g/day. The proportions of EPA and DHA increased significantly in all phospholipid pools examined: plasma EPA increased from 1.13 to 3.38% of total fatty acids; DHA increased from 2.33 to 4.08%; platelet EPA increased from 0.41 to 1.2%; and an increase of DHA from 1.64 to 3.07% was observed. Flaxseed products provided approximately 57% of total ALA intake, with canola oil providing an additional 19%. The results of this research demonstrated that providing a wide range of n-3 PUFA enriched products in a regular diet enabled individuals who do not habitually consume fish to benefit from an increased intake of n-3 PUFA without a radical modification to their normal habits. The researchers stated that increasing n-3 PUFA consumption from an early age may help prevent the onset of a variety of “lifestyle” diseases including atherosclerosis, diabetes, hypertension, and obesity.
