November 17, 2025

expert reaction to weight-loss drugs influencing brain signals linked to food cravings, as published in Nature Medicine

Scientists respond to article published in Nature Medicine exploring the link between weight-loss drugs and food cravings.

Dr Simon Cork, Senior Lecturer in Physiology, Anglia Ruskin University (ARU), said:

“I think some caution needs to be applied when journalists are reporting on this study.

“This study specifically looked at a marker of brain activity associated with periods of “binge eating” in patients with obesity associated with food preoccupation. This is important because this is a specific (and rare) condition associated with obesity. They found that in three patients, periods of intense preoccupation with food was associated with a characteristic change in brain activity in a region of the brain associated with reward (Nucleus accumbens).

“Subsequently, the authors found that in one patient, tirzepatide (Mounjaro) use was associated with an absence of such a signature for this type of activity for up to 4 months, before the effects seem to abate.

“The authors state that during this time the brain activity recorded in the nucleus accumbens was indistinguishable from the control state, which I interpret as meaning there was no suppression of brain activity beyond what is “normal”, but the increased brain activity associated with periods of food preoccupation (i.e., binge eating) are suppressed.

“We know from animal studies that directly record from neurons in this region of the brain that GLP-1 (the hormone that this medication is based) does suppress activity of this region of the brain, and this suppression is likely associated with the reduction in “food noise” that patients with obesity often report. It is also likely to be one of the reasons why this drug class is seeing increased interest in combating addictive conditions (such as alcohol and drug abuse).

“So, while this study is methodologically very interesting, it has to be clear that this is only one patient with a very specific condition that is associated with obesity and so shouldn’t necessarily be generalised to the entire population.”

‘Brain activity associated with breakthrough food preoccupation in an individual on tirzepatide’ by Wonkyung Choi et al. was published in Nature Medicine at 16:00 UK time on Monday 17th November

DOI: https://doi.org/10.1038/s41591-025-04035-5

Declared interests:

Dr Simon Cork: No interests to declare