Submitted to: Circulation
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 11/4/2003
Publication Date: 6/1/2004
Citation: Baer, D.J., Judd, J.T., Clevidence, B.A., Tracy, R. 2004. Dietary fatty acids affect circulating concentrations of markers of inflammation. Circulation. 79:969-973.
Interpretive Summary: We conducted a controlled dietary intervention study to determine the effect of dietary fatty acids and fats on markers of inflammation. Fifty normocholesterolemic men were fed six different controlled diets for five weeks each. The diets were enriched in 1) oleic acid, 2) stearic acid, 3) saturated fatty acids (a combination of lauric, myristic and palmitic), 4) two concentrations of trans fatty acids, and these diets were compared to a carbohydrates control diet. After consumption of each diet, plasma IL-6, fibrinogen, eselectin and c-reactive protein were measured. Diets enriched in saturated fatty acids and trans fatty acids tended to increase the concentration of these markers compared to a carbohydrate control diet and a diet enriched in oleic acid. These data help to define the potential role of diet in modulating risk for disease above and beyond the traditional cholesterol-based risk factors of coronary artery disease, and are important to food manufacturers, individuals at risk for cardiovascular disease, and physicians and allied health professionals who advise patients on issues related to diet and health.
Technical Abstract: Increased concentrations of some markers of inflammation have been identified as risk factors for coronary artery disease. While there are several factors that may effect the concentration of markers of inflammation, there are few data from controlled dietary interventions study that can help define the role of dietary fat on these important markers of risk for disease. A controlled feeding study was conducted to evaluate the role of dietary fat and specific fatty acids on modifying markers of inflammation. Fifty normocholesterolemic, healthy men were fed controlled diets for 5 wks. The diets provided 15 energy % (en%) protein, 39 en% fat, and 46 en% carbohydrate (CHO) in a randomized crossover design. Eight en% of fat or fatty acids was replaced across diets with the following: CHO (1:1 simple to complex); oleic acid (OLE); trans fatty acids (TFA); stearic (STE); TFA+STE (4 en% each); and C12:0-16:0 saturates (LMP). Blood samples collected during the 5th week were analyzed for fibrinogen, c-reactive protein, IL-6 and eSelectin. After consumption of the diet enriched in steric acid, fibrinogen concentration was higher than after consumption of the other diets. IL-6 concentration was lower after consumption of the OL diet compared to after consumption of the LMP, TFA and STE diets. C-reactive protein concentration was higher after consumption of the TFA diet compared to the CHO diet but c-reactive protein concentration was not different after consumption of the TFA and TFA/STE diets compared to after consumption of the LMP diet. Eselectin concentration was 9.6% higher after consumption of the TFA diet compared to the carbohydrate control diet. Consumption of the TFA but not the TFA/STE diet increased (5.6%) eselectin concentration compared to the LMP diet. These data provide evidence from controlled dietary interventions that diet, specifically fatty acids, can modulate markers of inflammation. Dietary fatty acids that raise LDL cholesterol (saturated and trans fatty acids) also tend to increase markers of inflammation. Further, although stearic acid has little impact on LDL cholesterol, it does appear to increase fibrinogen concentrations. These data are important to better understand the link between diet and inflammatory disease.