By: Elka Karl
Ghrelin, a hormone produced by the stomach cells, plays an important role in food intake, but little is known about how ghrelin concentrations are affected by dietary factors.
Twenty lean, healthy Dutch men were measured for appetite and concentrations of ghrelin, glucose, insulin and leptin and were frequently assessed for four-hour periods after varied liquid breakfast meals. Ghrelin concentrations decreased after the high-calorie simple carbohydrate breakfast by 41 percent; after the high-calorie complex carbohydrate breakfast by 33 percent; and after the low-calorie breakfast by 24 percent.
This randomized, double-blinded, crossover study showed that ghrelin concentrations were correlated with subjective measures of hunger and fullness. The percentage decrease in ghrelin between 0 and 30 minutes was inversely correlated with the percentage increases in insulin and glucose.
The researchers conclude that these results indicate ghrelin requires postgastric feedback, which may be regulated through insulin.
—American Journal of Clinical Nutrition, February 2005