Diabetes Care, Vol 9, Issue 3 244-249, Copyright © 1986 by American Diabetes Association
Effect of composition of mixed meals--low- versus high-carbohydrate content--on insulin, glucagon, and somatostatin release in healthy humans and in patients with NIDDM
M Gutniak, V Grill and S Efendic
Effects of a low-carbohydrate high-fat meal (LCM) versus a
high-carbohydrate low-fat meal (HCM) on insulin, glucagon, and somatostatin
release in nonobese healthy volunteers and in subjects with mild
non-insulin-dependent diabetes mellitus (NIDDM) were compared. The meals
were isocaloric. In the LCM, 26% of energy was supplied by carbohydrate,
51% by fat, and 23% by protein, whereas corresponding figures for HCM were
62, 22, and 16%. Hormonal responses were expressed as incremental areas
over baseline. In healthy volunteers the HCM had a significantly greater
effect on the insulin response than did the LCM. In contrast, in the
diabetic group the insulin response to HCM was markedly impaired and was of
the same magnitude as that to LCM. Glucagon release was significantly
augmented after LCM in the nondiabetic as well as in the diabetic group,
despite a pronounced and concomitant hyperglycemia in the latter. Moreover,
HCM tended to stimulate glucagon release but only in the diabetic subjects.
LCM and HCM induced a significant and sustained elevation of somatostatin
levels in both groups; these responses were not significantly influenced by
glucose tolerance or composition of meal. In conclusion, the present study
suggests that at least two islet dysfunctions--decreased insulin response
and enhanced glucagon release--characterize mild NIDDM. With a
high-carbohydrate meal, a severe impairment of insulin secretion and a
slight paradoxical glucagon release are observed. With a low-carbohydrate
fat-rich meal, beta-cell responsiveness seems to be intact, but alpha-cell
secretion is enhanced.