Isn’t it Time for Dietary Recommendations for Omega-3 Fatty Acids?
Omega-3 fatty acids are good for the brain and the heart. It is not surprising since long chain polyunsaturated fatty acid(LCPUFA) docosahexaenoic acid (DHA) makes up 97% of the LCPUFA present in the brain. DHA, along with its precursor eicosapentaenoic acid (EPA) are important for heart health. Triglycerides are found in the blood in a range of particle size. Supplementation with 4g EPA and 5g DHA daily for 12 wk has been shown to reduce serum triglycerides 26% (Oelrich and colleagues).
Fat cells are known as adipocytes. While scientists used to think the sole function of adipocytes was storage, this is not the case. Adipocytes also secrete hormones, adiponectin and leptin, which regulate energy metabolism and insulin resistance. In a new review, Gray and colleagues explore the role of omega-3 LCPUFA on body composition and weight management.
They write, “Current evidence suggests a positive, dose-dependent relationship between omega-3 fatty acid intake and circulating levels of adiponectin. In obese subjects, this may translate into a reduced risk of developing cardiovascular disease, metabolic syndrome and diabetes. In non-obese subjects, omega-3 is observed to decrease circulating levels of leptin.”
Eating diets imbalanced in long-chain fatty acids may also contribute to inflammation and elevated CRP levels. Reinders and colleagues reported that higher total serum omega-3 concentrations [eicosapentaenoic acid (EPA) + docoapentaenoic acid (DPA) and docosahexaenoic acid (DHA)], and DHA (%) are associated with lower CRP concentrations. α-linolenic acid (ALA) levels were not.
Given the accumulating evidence on the role of omega-3 LCPUFA in health, isn’t time to develop dietary recommendations for DHA and EPA?
Gray B, Steyn F, Davies PSW, Vitetta L. Omega-3 fatty acids: a review of the effects of adiponectin and leptin and potential implications for obesity management. 2013 Eur J Clin Nutr doi:10.1038/ejcn.2013.197
Oelrich B, Dewell A, Gardner CD. Effect of fish oil supplementation on serum triglycerides, LDL-cholesterol and LDL subfractions in hypertriglyceridemia adults. 2013 Nutr Metab CVD doi: 10.1016/j.numecd.2011.06.003
Reinders I, Virtanen JK, Brouwer A, Tuomainen T-P. Associations of serum n-3 polyunsaturated fatty acids with C-reactive protein in men. 2012 Eur J Clin Nutr doi:10.1038/ejcn/2011.195