Rise of plasma ghrelin with weight loss is not sustained during weight maintenance.
OBJECTIVE
Ghrelin is postulated to be an orexigenic signal that promotes weight regain after weight loss (WL). However, it is not known whether this putative effect of ghrelin is sustained after weight stabilization. The objective of this study was to investigate the relationship of plasma ghrelin concentrations to active WL and weight maintenance in obese subjects.


METHODS
This study was a randomized clinical trial, with a 12-month follow-up period. Obese Mexican-American women matched for age and BMI were randomized to a 12-month WL program (n = 25) or no intervention (controls, n = 23). Interventions included diet, exercise, and orlistat. Body weight and fasting ghrelin, leptin, insulin, and glucose concentrations were measured at baseline and 6 and 12 months.


RESULTS
The WL group lost 8.5% of body weight after 6 months and maintained the new weight for the next 6 months. Ghrelin concentrations increased significantly at 6 months but returned to baseline at 12 months. Baseline ghrelin concentrations were directly related to the degree of WL achieved after 12 months. Controls experienced no change in BMI or ghrelin levels. There were no associations between plasma ghrelin and leptin or insulin concentrations.


CONCLUSIONS
Consistent with previous results, ghrelin rises in response to WL, perhaps as a counterregulatory mechanism. However, the present results indicate that ghrelin concentrations return to baseline with sustained weight maintenance, suggesting that its effects are unlikely to regulate long-term energy balance. Baseline ghrelin concentrations are related to the degree of WL that can be achieved by active weight reduction.
Garcia
Jose M
JM
Translational Metabolism Unit, Division of Diabetes, Endocrinology, and Metabolism, Baylor College of Medicine, Houston, TX 77030, USA.
Iyer
Dinakar
D
Poston
Walker S C
WS
Marcelli
Marco
M
Reeves
Rebecca
R
Foreyt
John
J
Balasubramanyam
Ashok
A
D000328:Adult; D000704:Analysis of Variance; D015992:Body Mass Index; D001835:Body Weight / Q000502:physiology*; D005260:Female; D005500:Follow-Up Studies; D054439:Ghrelin; D006293:Health Promotion / Q000379:methods; D006801:Humans; D007328:Insulin / Q000097:blood; D007333:Insulin Resistance / Q000502:physiology; D020738:Leptin / Q000097:blood; D017058:Mexican Americans; D008875:Middle Aged; D009765:Obesity / Q000097:blood / Q000503:physiopathology / Q000628:therapy*; D036361:Peptide Hormones / Q000097:blood*; D011863:Radioimmunoassay / Q000379:methods; D013997:Time Factors; D049629:Waist-Hip Ratio; D015431:Weight Loss / Q000502:physiology*
D054439:Ghrelin; D007328:Insulin; D020738:Leptin; D036361:Peptide Hormones