On the other hand, it is emerging that previously unrecognized products of lipid metabolism may have profound effects on metabolic syndrome and potentially on the induction of diabetes. Palmitoleate has been recognized as an adipose-tissue derived lipid hormone that strongly stimulates muscle insulin action and suppresses hepatosteatosis (17). If palmitoleate acts as a lipid hormone in human is not known. In human, other fatty acids have been demonstrated to be altered in clinical conditions opposite to obesity. In fact, in cystic fibrosis patients, who are usually malnourished, we detected an increase in saturated and monounsaturated fatty acids (18) and a decrease in n-6 polyunsaturated fatty acids. C24:0 was positively correlated with BMI, plasma cholesterol and vitamin E, and significantly negatively correlated with oxysterols.Taken together, these data possibly identifies C24:0 as an indicator of adequate nutriture, coupled with the observation that C24:0 levels were reduced in patients with pancreatic insufficiency.