Regulation of intestinal immunity by dietary fatty acids

Dietary fatty acids are absorbed through the intestine and are fundamental for cellular energy provision and structural formation. Dietary fatty acids profoundly affect intestinal immunity and influence the development and progression of inflammatory bowel disease, intestinal infections and tumors. Although different types of fatty acids exert differential roles in intestinal immunity, a western diet, rich in saturated fatty acids with abundant carbohydrates and studied as high-fat diet (HFD) in animal experiments, disturbs intestinal homeostasis and plays a pathogenic role in intestinal inflammatory diseases. Here, we review recent findings on the regulation of intestinal immunity by dietary fatty acids, focusing on HFD. We summarize HFD-altered immune responses leading to susceptibility to intestinal pathology and dissect the mechanisms involving the impact of HFD on immune cells, intestinal epithelial cells and the microbiota. Understanding the perturbation of intestinal immunity by HFD will provide new strategies for prevention and treatment of intestinal inflammatory diseases.