Abstract: The prevalence of metabolic inflammatory syndrome (MIS) in the elderly is high, and imbalance of glucose and lipid homeostasis and insulin resistance are common in these patients. The novel compound, branched fatty acid esters of hydroxy fatty acids (FAHFAs), has effects of enhancing insulin sensitivity and anti-inflammatory, among which the content of palmitic acid hydroxy stearic acid (PAHSA) is the highest. The level of PAHSA in vivo is primarily regulated by the carbohydrate response element binding protein (CHREBP), which exerts a biological effects via G protein coupled receptor 120 (GPR120). This review mainly describes the research progress on the mechanism of PAHSA in metabolic inflammatory syndrome.