Impact of dietary fat on gut microbiota and low-grade systemic inflammation: mechanisms and clinical implications on obesity

Int J Food Sci Nutr. 2018 Mar;69(2):125-143. doi: 10.1080/09637486.2017.1343286. Epub 2017 Jul 4.


Dietary fat strongly affects human health by modulating gut microbiota composition and low-grade systemic inflammation. High-fat diets have been implicated in reduced gut microbiota richness, increased Firmicutes to Bacteroidetes ratio, and several changes at family, genus and species levels. Saturated (SFA), monounsaturated (MUFA), polyunsaturated (PUFA) and conjugated linolenic fatty acids share important pathways of immune system activation/inhibition with gut microbes, modulating obesogenic and proinflammatory profiles. Mechanisms that link dietary fat, gut microbiota and obesity are mediated by increased intestinal permeability, systemic endotoxemia, and the activity of the endocannabinoid system. Although the probiotic therapy could be a complementary strategy to improve gut microbiota composition, it did not show permanent effects to treat fat-induced dysbiosis. Based upon evidence to date, we believe that high-fat diets and SFA consumption should be avoided, and MUFA and omega-3 PUFA intake should be encouraged in order to regulate gut microbiota and inflammation, promoting body weight/fat control.

Keywords: High-fat diets; lipopolysaccharide; metabolic endotoxemia; monounsaturated fatty acid; polyunsaturated fatty acids; probiotics.

Publication types

  • Review

MeSH terms

  • Animals
  • Diet, High-Fat / adverse effects*
  • Dysbiosis / diet therapy
  • Dysbiosis / etiology*
  • Dysbiosis / microbiology
  • Dysbiosis / physiopathology
  • Endotoxemia / etiology*
  • Endotoxemia / immunology
  • Endotoxemia / microbiology
  • Endotoxemia / prevention & control
  • Enteritis / etiology*
  • Enteritis / immunology
  • Enteritis / microbiology
  • Enteritis / prevention & control
  • Evidence-Based Medicine*
  • Gastrointestinal Microbiome
  • Humans
  • Intestines / immunology*
  • Intestines / microbiology
  • Intestines / physiopathology
  • Obesity / etiology*
  • Obesity / immunology
  • Obesity / microbiology
  • Obesity / physiopathology
  • Permeability
  • Probiotics / therapeutic use
  • Synbiotics / administration & dosage
  • Weight Gain