Background: The amount and type of fat in the diet influence the development of obesity and related inflammatory activity. Knowledge of the possible influence of dietary habits on circulating adiponectin, a molecule with putative antiinflammatory properties, may be helpful in preventing atherosclerosis and type 2 diabetes.
Methods: The association between dietary fat, as inferred from plasma fatty acid composition (gas-liquid chromatography), and circulating adiponectin (RIA) was evaluated in 116 healthy individuals.
Results: The proportion of saturated fatty acids in plasma was significantly associated with circulating adiponectin concentration (r = -0.24; P = 0.01). Specifically, percentage of palmitic acid (C16:0) was significantly associated with lower adiponectin concentration (r = -0.28; P = 0.002), particularly among women (r = -0.37; P = 0.02) and nonsmokers (r = -0.30; P = 0.007). Percentage of myristic acid (C14:0) was also significantly associated with lower adiponectin among nonsmokers (r = -0.26; P = 0.02) and women (r = -0.39; P = 0.01). The other fatty acids were not significantly associated with adiponectin except for eicosanoic acid (C20:1 omega-9), which was significantly and positively associated with adiponectin in all individuals (r = 0.23; P = 0.01). This latter association was most significant in smokers (r = 0.43; P = 0.007). In a multivariate regression analysis to predict circulating adiponectin, after controlling for age, body mass index, waist-to-hip ratio, and the individual remaining fatty acids, the percentages of palmitic (P = 0.005) and eicosanoic acid (P = 0.03) contributed independently (6% and 3%, respectively) to adiponectin variance. Among nonsmokers, the percentages of palmitic acid (P = 0.01) and omega-3 fatty acids contributed 8% and 7%, respectively, to adiponectin variance. Among smokers, the percentage of eicosanoic acid (P = 0.03) contributed to 10% of adiponectin variance, independently of body mass index, age, waist-to hip ratio, and the remaining individual fatty acids.
Conclusions: Saturated and omega-3 fatty acids of dietary origin (as inferred from plasma fatty acid concentration) are associated with circulating adiponectin concentrations in healthy humans. The proportion of eicosanoic acid also appears to be positively associated with circulating adiponectin. The knowledge of how these interactions occur may be helpful in the planning of dietary measures aimed at the modulation of inflammatory activity.