Ozempic face: why your face looks hollow when you lose weight

Twenty patients, two head scans each, one before treatment and one after. On that small group an American team measured for the first time, in 2025, what the papers have spent two years calling "Ozempic face": after an average loss of eleven kilos, the volume of the middle of the face had fallen by 9%.

The figure is modest and the study small. Its merit is to put a measurement where there were only celebrity before-and-after photos, and to say where the change sits: in the fat lying just beneath the skin.

Ozempic face is a headline, not a diagnosis

"Ozempic face" is not a medical term. The phrase spread through the American press in early 2023, then facial surgeons picked it up in their journals, in inverted commas, to describe what patients were coming in to show them: cheeks less full, hollowed temples, skin that looks a size too big for what it covers. Two short papers from that year, in the Journal of Plastic, Reconstructive & Aesthetic Surgery and in Facial Plastic Surgery, describe it without putting numbers on it. In the UK, "Mounjaro face" has followed close behind and is now searched for several thousand times a month.

The name is misleading in any case. Ozempic (semaglutide) is a medicine for type 2 diabetes; Wegovy (semaglutide) and Mounjaro (tirzepatide) are the ones prescribed for weight management. None of the three lists a change in facial appearance among the side effects in its UK product information. Everything suggests that the hollowing goes with the weight loss itself.

What imaging has measured

The study, published in Otolaryngology-Head and Neck Surgery, went through the records of a university hospital to find patients on a GLP-1 medicine who had, for unrelated reasons, had a CT or MRI scan of the head both before and after starting treatment. There were twenty of them, with a median age of 54.

The volume of the midface had dropped by a median of 9%. The superficial fat, the layer that gives the cheekbones their roundness, had shrunk by 11%, and that loss tracked the number of kilos lost. The deep fat varied too much from one patient to another to draw a conclusion. From this the authors derive a rule of thumb: about 7% less facial volume for every ten kilos lost.

Twenty people, one centre: these figures give a first idea and nothing more. They do not say who will be affected.

Why it shows more on the face

Because the face has nowhere to hide what it loses. A few millimetres less fat around the waist goes unnoticed. On the cheekbones it changes the contours, shifts the shadows and leaves the skin slacker.

Age plays a part too. Past forty, skin has lost some of its elasticity and does not spring back as readily around a shrinking volume.

Then there is the scale of the loss. In the STEP 1 trial, participants treated with semaglutide 2.4mg lost an average of 14.9% of their weight in 68 weeks. Few diets produce a change that large in so short a time.

The case for a direct effect on skin

A review published in 2025 in Endocrine suggests that the story may not end with fat. Skin cells carry GLP-1 receptors, and the authors describe, from laboratory work, several mechanisms by which these medicines might slow the production of collagen.

It is a hypothesis, and the authors present it as one. No study has compared the skin of people who lost the same amount of weight with and without treatment. Until that comparison exists, there is no way to separate what belongs to the drug from what belongs to the kilos.

Muscle, the other silent loss

Fat never leaves alone. In the STEP 1 subgroup whose body composition was measured, 140 participants, fat mass fell by 19.3% and lean mass by 9.7%, according to the analysis published in the Journal of the Endocrine Society. A review in Diabetes, Obesity and Metabolism notes wide differences from one trial to the next: lean mass accounts for about 15% of the weight lost in some, 40 to 60% in others.

Those measurements concern the whole body, not the face, and lean mass is not the same thing as muscle. They are a reminder that a figure that shrinks fast also loses some of its frame, the subject of a separate article: Ozempic and muscle loss, and how to limit it.

So what can food do?

No food decides where the body draws its fat from, and no study shows that a particular diet preserves the volume of the cheeks. What food can do is avoid adding undernourishment to the weight loss.

When appetite falls, quantities fall, and protein with them. Protein contributes to the maintenance of muscle mass. The UK reference intake for a healthy adult is 0.75g per kilo of body weight a day; during weight loss, what you need is a matter to discuss with your prescriber or a registered dietitian. In practice it comes down to having a source of protein at every meal, breakfast included: an egg, dairy, fish, chicken, beans or lentils. Our GLP-1 diet guide gives the orders of magnitude.

Drinking regularly matters as well, all the more because the digestive side effects of the early weeks can lead to dehydration, as the patient leaflets point out. Water will not, for all that, give back lost volume.

For the rest, the question is one for a clinician. If your face is changing quickly, if tiredness is setting in, if you are eating very little, your prescriber needs to know. A dermatologist can examine the skin itself. As for the fillers and other cosmetic procedures discussed in the specialist journals, they belong in a consultation with a properly qualified practitioner, not in an article.

What nobody knows yet

Does the face regain its volume if the weight returns? No study has measured it, though we do know how often the weight itself comes back, as set out in coming off Mounjaro or Wegovy. Do GLP-1 medicines hollow the face more than surgery or a diet, kilo for kilo? No comparison exists. Does one of the three medicines leave more of a mark than the others? Nothing allows us to say; the imaging study ties the change to the kilos lost, not to a molecule.

"Ozempic face" will no doubt stay in the language, because the phrase works. It describes not so much a side effect as the visible trace of a large weight loss. Our guide to GLP-1 side effects covers those that do appear in the product information, including hair loss, which follows a similar logic and is quantified in the articles on Wegovy side effects and Mounjaro side effects.

This article is for information only and is no substitute for advice from a healthcare professional. Never change your treatment without talking to your doctor.