A new Japanese study has shown that the effectiveness of GLP-1 receptor agonists, such as Ozempic, depends on the predominant reasons for a person’s overeating. The findings were published in Frontiers in Clinical Diabetes and Healthcare.

Researchers observed 92 patients with type 2 diabetes who were prescribed this therapy. Participants were surveyed about their eating behaviors—whether they tended to eat in response to emotions, external cues (such as the sight or smell of food), or internal sensations of hunger. Their condition was monitored at the start of treatment, after three months, and after one year.

Overall, most participants experienced weight loss, better blood sugar control, improved lipid profiles, and reduced fat mass while maintaining muscle mass. However, the study revealed important differences. For those who tended to overeat in response to external cues, treatment was most effective: they lost more weight and maintained the results longer. Their tendency toward “external overeating” significantly decreased and remained low even after a year.

A very different picture was seen in people with pronounced emotional overeating. Despite therapy, their weight loss was less significant, and changes in eating behavior were short-lived. After some time, levels of emotional and restrictive overeating returned to their initial values.

The researchers emphasize that understanding the factors driving overeating may help predict how effective GLP-1 therapy will be. These findings could support a more personalized approach in the future—for example, combining medication with psychological support if emotional overeating predominates.

The authors note that the study was observational and based on self-reported data, which may affect accuracy. Nevertheless, the results highlight an important link between eating behavior type and response to next-generation weight-loss medications.