Trepidation with blood tests among men may result in fewer routine screening and examination of their cardiovascular risk factors. Associations between fecal microbiota and serum cholesterols have not been well-established. The aim of this study was to explore such association in order to determine the potential of fecal microbiota as a non-invasive alternate predictor of serum cholesterols. Secondary data from a cross-over trial were analyzed. Associations between fecal microbiota, mainly Bifidobacterium and Clostridial group, of healthy men (n = 16) and their total cholesterols, low and high-density lipoprotein cholesterols (LDL-C and HDL-C) were assessed using generalized estimating equations, adjusted for diet intervention, diet order, frequency of defecation and flatulence level. For every two-fold increase in fecal Bifidobacterium, geometric mean of LDL-C increases by a factor of 1.23 (95% CI: 1.01, 1.49) whilst that of HDL-C increases by a factor of 1.07 (95% CI: 1.03, 1.10). For every two-fold increase in Clostridial group (C. ramosum, C. spiroforme and C. cocleatum), geometric mean of HDL-C decreases by a factor of 1.10 (95% CI: -1.16, -1.03). No association was found between total bacteria and serum cholesterols. Fecal Bifidobacterium spp. and Clostridium spp., are potential non-invasive surrogate markers of men's serum cholesterols.
Keywords: cardiovascular risk factors; gastrointestinal microbiota; health-promoting microbes; non-invasive diagnostics; personalized healthcare; probiotics.