Study: Semaglutide Sustains Lower Calorie Intake for More Than a Year

Philadelphia — Individuals using semaglutide for weight management kept eating markedly fewer calories even after 60 weeks on the drug, shedding light on how the drug aids both early weight loss and sustained maintenance. The research, appearing in the American Journal of Clinical Nutrition and spearheaded by scientists from Penn’s Center for Weight and Eating Disorders together with Penn Metabolic Medicine, ranks among the pioneering investigations of semaglutide’s prolonged influence on eating habits past the first few months of therapy.

Scientists observed that although the drug’s initial curb on appetite and food‑related thoughts waned somewhat over time, the semaglutide group still ingested considerably fewer calories than the placebo cohort beyond the one‑year mark.

“Patients often fear the drug has lost its effect when hunger creeps back after the initial months,” explained Jena S. Tronieri, PhD, lead investigator and senior research scientist at Penn Medicine’s Center for Weight and Eating Disorders. “Our data reveal that even if those feelings resurface, semaglutide still curbs food intake. This ongoing calorie reduction seems central to preserving weight loss over the long haul.”

Assessing dietary intake

The 60‑week study recruited 120 adults classified as overweight or obese. Each participant was assigned either a weekly 2.4 mg injection of semaglutide or a matching placebo, and all received routine lifestyle coaching emphasizing nutritious eating and regular exercise.

Baseline measurements and follow‑up assessments at weeks 20, 40, and 60 each involved a five‑hour lab session. After consuming a fixed breakfast, participants were given lunch and instructed to eat to comfortable satiety, while investigators precisely tallied the calories ingested.

Relative to the placebo group, those on semaglutide showed a steady reduction in caloric intake across the trial. In total, the semaglutide arm ate roughly 24 %–30 % fewer calories than the placebo arm at each check‑point up to week 60.

Weight loss persisted amid lowered calorie consumption

Individuals receiving semaglutide shed a meaningful amount of weight, dropping an average of 15.1 % of their starting mass after 60 weeks. In contrast, the placebo group lost only about 3.4 % of their initial weight by the same point.

The trial also gauged hunger, satiety, and food preoccupation (often termed “food noise”). In the initial 20 weeks, semaglutide users reported reduced hunger, tighter appetite regulation, and fewer food‑related thoughts. Yet by weeks 40 and 60, the gaps between the drug and placebo groups on several of these self‑reported metrics had faded to non‑significance.

“This research underscores a crucial gap between how individuals perceive their hunger and what they actually consume,” noted Thomas A. Wadden, PhD, professor of psychology in psychiatry and former head of Penn’s Center for Weight and Eating Disorders. “Patients on semaglutide often experience a sharp drop in hunger and food‑related thoughts at the outset. When those sensations fade, some might mistakenly think the drug has lost its potency.”

“Our findings indicate that, over time, users may notice a mild resurgence of appetite cues while still benefiting from the drug’s ongoing calorie‑cutting effect — essential for sustaining their reduced weight,” said Tronieri. “Recognizing this can shape realistic expectations and may motivate continued therapy, in line with FDA approval and the guidance of many professional organizations.”

Editor’s Note: This investigation received partial funding from a Novo Nordisk research grant administered through the NNI Investigator‑Sponsored Studies Program for the University of Pennsylvania. Novo Nordisk had no involvement in the study’s design, execution, data analysis, or manuscript preparation. The conclusions and interpretations presented herein are solely those of the authors and do not necessarily reflect the stance of Novo Nordisk.