Related Experiment Video
Updated: Aug 7, 2026

A RAPID Method for Blood Processing to Increase the Yield of Plasma Peptide Levels in Human Blood
Published on: April 28, 2016
Fasting ghrelin does not predict food intake after short-term energy restriction
Wendy A M Blom1, Monica Mars, Henk F J Hendriks
1TNO Quality of Life, Business Centre Nutrition, Zeist, The Netherlands.
Objective:
To study the role of ghrelin as a hunger signal during energy restriction and to test the hypothesis that changes in fasting leptin concentrations during energy restriction are associated with changes in fasting ghrelin concentrations.
Research Methods And Procedures:
Thirty-five healthy, lean men (23 +/- 3 years of age; BMI: 22.3 +/- 1.6 kg/m(2)) participated in a controlled intervention study. Fasting ghrelin and leptin concentrations were measured before and after 2 days of 62% energy restriction and after a 2-day period of ad libitum food intake. Energy intake during the latter period was assessed.
Results:
On average, ghrelin concentrations did not change (0.05 mug/liter; 95% confidence interval, -0.03; 0.12) during energy restriction. Changes in ghrelin concentration during energy restriction were not associated with energy intake during the ad libitum period (r = 0.07; not significant). Ad libitum energy intake was, however, associated with the change in ghrelin concentrations during the same period (r = -0.34; p = 0.05). Ghrelin and leptin concentrations were not associated. In addition, the ratio of percentage changes in ghrelin and leptin during energy restriction was not correlated with ad libitum food intake after energy restriction (r = -0.26; p = 0.14).
Discussion:
Fasting ghrelin concentrations did not rise after a 2-day energy restriction regimen. Moreover, changes in ghrelin concentrations during energy restriction were not associated with subsequent ad libitum food intake, suggesting that fasting ghrelin does not act as a hunger signal to the brain. The data did not support our hypothesis that leptin suppresses ghrelin levels.
Related Concept Videos
Regulation of Food Intake
Metabolic States of the Body: Fasting and Starvation
Metabolic States of the Body: The Postabsorptive State
Initially, glycogen stored in the liver is broken down to release glucose into the bloodstream, while glycogen in the muscles is broken down to supply glucose for energy directly within the muscle cells. As glycogen stores diminish,...
Hypoglycemia and Glucagon
Glucagon-like Receptor Agonists
GLP-1, when administered in high doses intravenously, triggers insulin secretion, inhibits glucagon release, slows gastric emptying, reduces food intake, and restores normal insulin secretion. However, its rapid inactivation by the...
Metabolic States of the Body: The Absorptive State
