In human studies, conducted on three groups of people: obese volunteers, endurance trained athletes and people with type 2 diabetes, it has been shown that at rest, total muscle ceramide content did not differ between all groups, however, the content of C18:0-Cer in T2D patients was significantly higher than in athletes and it was positively associated with BMI and inversely related to insulin sensitivity [178]. Here, INS is linked to type 2 diabetes mellitus.