Research Paper Title

The Ghrelin and Leptin Responses to Short-term Starvation vs a Carbohydrate-free Diet in Men with Type 2 Diabetes; A Controlled, Cross-over Design Study.

Background

The researchers have recently reported the 24 hour glucose, insulin and glucagon responses to a 72 hour fast compared to a 72 hour macronutrient-sufficient, carbohydrate-free diet in men with type 2 diabetes. The 72 hour time period was used because it is the time required for the major metabolic adjustments to a lack of food to be instituted. As part of that study, ghrelin and leptin responses were monitored.

Methods

Twenty-four-hour total ghrelin and overnight fasting leptin concentrations were determined in males with type 2 diabetes when ingesting a standard, mixed meal diet (control), followed by a carbohydrate-free diet for 72 hours or were starved for 72 hours, using a crossover design.

Results

A rise in ghrelin concentration before and a decrease after meals was present when the standard diet was ingested. However, in contrast to literature reports in normal subjects, a circadian variation was not apparent. Meal related changes were absent with starvation. A carbohydrate-free diet resulted in a daylong decrease in ghrelin. It also resulted in a 19% decrease in the overnight fasting leptin concentration. Leptin was decreased 54% with total starvation.

Conclusion

Ingestion of a typical mixed-meal diet results in meal-related changes in ghrelin similar to those reported in normal subjects, although the circadian rhythm was not apparent. Except for the lack of meal-related changes, starvation did not change the concentration. A carbohydrate-free, high fat diet resulted in a daylong suppression of ghrelin. The leptin concentration was decreased by both the carbohydrate-free diet and starvation.

Reference

Nuttall, F.Q., Almonkayyad, R.M. & Gannon, M.C. (2016) The Ghrelin and Leptin Responses to Short-term Starvation vs a Carbohydrate-free Diet in Men with Type 2 Diabetes; A Controlled, Cross-over Design Study. Nutrition and Metabolism. 13(47). DOI: 10.1186/s12986-016-0106-x.