Systematic review of saturated fatty acids on inflammation and circulating levels of adipokines.

Diet is one factor that plays a part in coronary heart disease risk through multiple biological mechanisms including subclinical inflammation. In this review, we aimed to systematically assess and summarize evidence regarding the association of saturated fatty acids (SFAs) with inflammatory markers and adipokines. An electronic search of the literature was conducted up to September 2010 using Medline, Scopus, Web of Science, and Science Direct (updated from September 2010 to August 2011 through Medline). Original studies that were written in Portuguese, English, Spanish, or French, and addressed the effects of SFA (not dietary sources or SFA-rich diets) on inflammatory markers or adipokines in adult populations were considered eligible. Data from 15 studies providing adjusted estimates were extracted. The publication year varied from 1995 to 2010 and the sample size from 54 to 4900. Most studies were cross sectional, with 3 studies using a prospective design. Twelve studies assessed total SFA, and 3 studies considered their subtypes, which were measured through dietary assessments (11 studies) or in blood samples (4 studies). Significant positive associations were observed between SFA and soluble intercellular adhesion molecule-1 and interleukin-6, whereas no significant associations were observed with E-selectin, tumor necrosis factor α, granulocyte-macrophage colony-stimulating factor, fibrinogen, and adiponectin. For high-sensitivity C-reactive protein, 2 studies showed significant positive associations, whereas 3 studies reported no significant associations. One study reported a significant inverse association of SFA with leptin, although the other 3 found no significant associations. Based on this systematic review, a potential positive association of SFA with high-sensitivity C-reactive protein but not with adipokines is suggested, which should be confirmed by future research.