Low fasting insulin levels in Eskimos compared to American Indians: are Eskimos less insulin resistant?

The prevalence of diabetes is relatively low among Eskimo people in contrast to that in other Native American populations. The reasons for this may be partially explained by differences in the occurrence of insulin resistance. In this report we compare fasting insulin levels, which correlate with insulin resistance, in Alaskan Eskimo subjects to those among American Indians. After adjusting for age, gender, and body mass index, and using identical laboratory methods, we found significantly lower insulin levels among Eskimo compared with Indian participants with normal glucose tolerance. Among Eskimos insulin levels increased with increasing body mass index, were higher for women than men, and did not appreciably change with age. Our data suggest that among Eskimo people insulin resistance may be less prevalent or severe than among American Indians, but that obesity is associated with increased insulin resistance. Future analyses will examine the association between insulin levels and other correlates of the insulin resistance syndrome. We hope that by further characterizing insulin resistance or sensitivity among Eskimo people, specific recommendations can be made that will lead to cardiovascular risk factor reduction.