Objective: The aim of this study was to determine whether the hormone changes following weight loss are proportional to the degree of weight loss and to starting BMI. Methods: A very low-energy diet was used to achieve 15% weight loss. Fasting and postprandial gut hormones and leptin were measured during a meal test at baseline and at 5% (1%), 10% (2%), and 15% (2.5%) weight loss. Linear mixed-effects models were used to analyze hormone changes. Results: From baseline to 5% weight loss, decreases were seen in fasting concentrations of leptin (−8.25 ng/mL; p < 0.001), amylin (−21.3 pg/mL; p < 0.001), and glucagon-like peptide 1 (−59.55 pg/mL; p < 0.001). There was a small further reduction in leptin between 5% and 15% weight loss (−1.88 ng/mL; p = 0.019) but not in glucagon-like peptide 1 and amylin. Fasting ghrelin showed a significant increase at 10% weight loss (41.64 pg/mL; p = 0.002), with a nonsignificant increase from 10% to 15% loss (26.03 pg/mL; p = 0.065). Postprandial changes in hormone levels were variable. There was no correlation between baseline weight and the degree of hormone changes. Conclusions: The majority of changes in fasting gut hormones and leptin occurred in early weight loss, with minor further changes up to 15% weight loss. Starting weight did not affect the degree of hormone change.
Funding
KE was supported by the Australian Government Research Training Scheme. PS is supported by an Investigator Grant from the National Health and Medical Research Council (1178482).