Relationship of dietary fat and serum cholesterol ester and phospholipid fatty acids to markers of insulin resistance in men and women with a range of glucose tolerance
Jc. Lovejoy et al., Relationship of dietary fat and serum cholesterol ester and phospholipid fatty acids to markers of insulin resistance in men and women with a range of glucose tolerance, METABOLISM, 50(1), 2001, pp. 86-92
High-fat diets are associated with insulin resistance, however, this effect
may vary depending on the type of fat consumed. The purpose of this study
was to determine the relationship between intakes of specific dietary fatty
acids (assessed by 3-day diet records and fatty acid composition of serum
cholesterol esters [CEs] and phospholipids [PLs]) and glucose and insulin c
oncentrations during an oral glucose tolerance test (OGTT). Nineteen men an
d 19 women completed the study. Nine subjects had type 2 diabetes or impair
ed glucose tolerance. Pasting insulin correlated with reported intakes of t
otal fat (r = .50, P < .01), monounsaturated fat (r = .44, P < .01), and sa
turated fat (r = .49, P < .01), but not with trans fatty acid intake (r = .
11, not significant [NS]). Pasting glucose also correlated with total (r =
.49, P < .05) and monounsaturated fat intakes (r = .37, P < .05). In multiv
ariate analysis, both total and saturated fat intake were strong single pre
dictors of fasting insulin (R-2 <similar to> .25), and a model combining di
etary and anthropometric measures accounted for 47% of the variance in fast
ing insulin. Significant relationships were observed between fasting insuli
n and the serum CE enrichments of myristic (C14:0), palmitoleic (C16:1), an
d dihomo-gamma -linolenic (C20:3n-6) acids. In multivariate analysis, a mod
el containing CE 14:0 and percent body fat explained 45% of the variance in
fasting insulin, and C14:0 and age explained 30% of the variance in fastin
g glucose. PL C20:3n-6 explained 30% of the variance in fasting insulin, an
d a model including PL C18:1n-11 cis, C20:3n-6, age and body fat had an R2
of .58. In conclusion, self-reported intake of saturated and monounsaturate
d fats, but not trans fatty acids, are associated with markers of insulin r
esistance. Furthermore, enhancement of dihomo-gamma -linolenic and myristic
acids in serum CE and PI presumably markers for dietary intake, predicted
insulin resistance. Copyright (C) 2001 by W.B. Saunders Company.