Influence of GLP-1–based pharmacotherapies on eating behaviour, appetite, and energy intake in adults with overweight or obesity: a systematic review and meta-analysis

Introduction:

Whilst GLP-1–based pharmacotherapies achieve clinically significant weight loss, their influence on eating behaviour is unknown.

Methods:

This systematic review examined the effects of GLP-1–based pharmacotherapies on eating behaviour, appetite, and energy intake in adults (≥ 18 years) with overweight or obesity (BMI ≥ 25 kg/m2) without major comorbidities. MEDLINE, PsycINFO, EMBASE and Web of Science were searched on 4th November 2025. Risk of bias was assessed, and meta-analyses were conducted for energy intake and overall appetite suppression, with other outcomes synthesised qualitatively.

Results:

Twenty-five articles involving 4,060 participants were included (64% female, mean age = 44 years, mean BMI = 36.7 kg/m2). Four studies were deemed low risk of bias. A reduction in energy intake was observed (SMD = −0.775, 95% CI = −1.21 to −0.34, P = .002), although heterogeneity was high (I2 = 82.7%) and the prediction interval included no effect. A small increase in appetite suppression was also observed (MD = 7.800, 95% CI = 3.74 to 11.86, P = .001). Qualitative findings suggested reductions in food craving and some measures of food reward. Nausea was more frequent with active treatment and may have influenced the observed effects or increased awareness of treatment allocation.

Conclusion:

GLP-1–based pharmacotherapies may reduce short-term energy intake and appetite. However, the magnitude and consistency of these effects remain uncertain because of substantial heterogeneity, imputation of variance data, and variability in outcome assessment. Evidence relating to food craving, food preferences and other eating behaviours require further investigation.