A STUDY FROM St Vincent’s University Hospital Dublin has challenged the belief that weight loss medications including Ozempic, Wegovy, and Monjaro work just by making users feel more full.

A randomised controlled trial of 30 patients which examined the family of medications found that there is a strong relationship between the increase in metabolic activity – the burning of calories – caused by a once-daily treatment and the amount of weight lost.

It also found that people who had a low metabolic activity before they started treatment benefited the most from it.

Professor Donal O’Shea, who led the study, said that the study “challenges the main narrative that these treatments simply make you eat less, and that any action on energy burn is minimal”.

“It always seemed oversimplistic to me that these new treatments were just making people eat less. The findings provide science to support the fact that treatment of obesity is not simply to eat less and move more – that’s the prevention piece. Treatment is more complex than that,” he said.

“Safe medical treatment for obesity is still in its infancy and we need to understand fully how the treatment works.”

Drugs such as Ozempic, Wegovy and Monjaro are based on the hormone Glucagon-like peptide-1 (GLP-1). They are commonly used to treat Type-2 diabetes, and have been modified to be used as a long-term weight-loss treatment.

The drugs work by mimicking a naturally-occuring hormone. As these hormone levels rise, messages to the patients brain communicate that the body is full. They also slow down digestion.

The study ‘GLP‐1 therapy increases visceral adipose tissue metabolic activity: lessons from a randomized controlled trial in obstructive sleep apnea,’ was co-authored by Professor Silke Ryan, SVUH, funded by the Health Research Board and supported by University College Dublin.