Increased adiposity is linked to altered levels of biologically active proteins, including the hormones adiponectin and leptin. Adiponectin is negatively correlated with obesity, with lower levels associated with increased risk of death or myocardial infarction (MI). Conversely, leptin levels are positively correlated with obesity, with higher levels identified as an independent risk factor for CVD. Researchers reviewed animal and human data relating to the effects of Omega-3 (n-3) fatty acids on adiponectin and leptin. The beneficial effects of n-3 polyunsaturated fatty acids (PUFA) are not just due to the modulation of the amount and types of eicosanoids produced, but also the regulation of intracellular signaling pathways, transcription factor activity, and gene expression, resulting in the regulation of inflammation, platelet adhesion, blood pressure regulation, heart rhythm and triglycerides. The majority of available studies assessing the effect of n-3 fatty acids on adiponectin reported n-3 intake induced statistically significant increases in adiponectin levels in both animal and human models. These include studies with subjects in normal weight range, overweight and obese. Results were consistent between healthy individuals and those investigating hyperlipidemic patients with 2TDM, or recent history of MI. Of the limited studies on n-3 and circulating leptin utilizing stable weight participants, the majority demonstrated either minimal change or a reduction in leptin levels.
B Gray, F Steyn, PSW Davies and L Vitetta. Omega-3 fatty acids: a review of the effects on adiponectin and leptin and potential implications for obesity management. European Journal of Clinical Nutrition (2013) 67, 1234-1242