Independent Effects Of Bmi, Crp And Carotenoids, But Not Diet Change, On Lps Binding Protein Concentrations

Mediterranean diets are known to have anti‐inflammatory effects as compared with Western diets, but the etiology of this association is not known. One factor that could contribute to the chronic, low‐grade pro‐inflammatory state that is associated with Western diets is exposure to intestinal bacteria. Bacterial lipopolysaccharide exposures elicit an immune response that is mediated by lipopolysaccharide binding protein (LBP). LBP helps concentrate lipopolysaccharide at membrane toll‐like receptors. In this study, blood samples were obtained from 120 subjects at high risk for colon cancer before and after randomization to either a Mediterranean or Healthy Eating diet for 6 months. There was no significant change in serum LBP concentrations in either diet arm. In evaluating influential factors at baseline, there was a significant inverse correlation between LBP and serum carotenoids (r = ‐0.299, p<0.001), and positive correlations with C‐reactive protein (r =0.323, p<0.001) and BMI (r =0.322, p=0.004). These three factors had independent effects and accounted for 14% of the variability in serum LBP concentrations at baseline. Since the study was designed to maintain baseline weight, it was not possible to evaluate the effects of weight change on LBP levels. Both interventions did increase serum carotenoids, but the study was only 6 months long which could limit any diet intervention effects. Further research should be designed to delineate the relative effects of diet quality and body weight on serum LBP concentrations. Research on methods to quantify bacterial exposures more directly is also needed to enable studies of the links between intestinal microflora, systemic pro‐inflammatory states and cancer. Grant Funding Source : Supported by NIH grants RO1 CA120381 and P50 CA130810