Ozempic Butt: What It Is, Why It Happens and How to Fix It

In this guide13 sections

1. Key Points
2. What Is Ozempic Butt?
3. Why Does Ozempic Cause a Flat, Saggy Bum?
4. Who Is Most Likely to Get Ozempic Butt?
5. How to Avoid Ozempic Butt
6. How to Fix Ozempic Butt: Treatments Compared
7. What If You Don’t Have Enough Fat for a BBL After Weight Loss?
8. Ozempic Butt Before and After
9. When Can You Have Surgery After Ozempic or Mounjaro?
10. Ozempic Body: Face, Breasts, Arms and Thighs
11. Frequently Asked Questions
12. Why Choose Centre for Surgery for Buttock Surgery After Weight Loss?
13. References

Weight-loss injections have changed what is possible for people who have struggled with their weight for years. Losing 15 or 20 per cent of your body weight within a year or so is now common, and with it has come a new set of nicknames for the changes it can leave behind. After Ozempic face, the one we hear about most in clinic is Ozempic butt: a bottom that looks flatter, emptier and lower than it did before, sometimes with loose, crinkled skin and a deeper fold underneath.

This guide explains what Ozempic butt, or Ozempic bum as most people in the UK search for it, actually is, why it happens on Ozempic, Wegovy and Mounjaro, who is most likely to get it, and how to reduce the risk while you are still losing weight. It then compares the treatments that can fix it, from exercise and filler to a Brazilian butt lift and a buttock lift, and explains what to do if you no longer have enough spare fat for a BBL. It sits alongside our wider guide to loose skin after weight loss.

What Is Ozempic Butt?

Ozempic butt is not a medical diagnosis. It is a popular name for a change in the shape of the buttocks after significant weight loss, and it caught on because weight-loss injections made that kind of weight loss so common. A plastic surgeon would describe the same thing as volume loss and ptosis (sagging) of the buttock. The name comes from Ozempic, the semaglutide injection licensed for type 2 diabetes, but the same change happens with Wegovy, which is semaglutide licensed for weight management, and with Mounjaro, which is tirzepatide. Whatever you call it, it is the same problem.

What Does Ozempic Bum Look Like?

Most people notice it in the fit of their clothes before anything else: jeans with room to spare in the seat, or leggings that wrinkle where they used to sit smoothly. The typical signs are:

• A flatter bottom, especially across the upper half of the buttock, which loses its rounded projection.
• Sagging, with the lowest point of the buttock sitting lower than it did.
• A deeper or longer crease under the buttock, sometimes with a second fold or a roll of skin below it, similar to a banana roll.
• Loose, crêpey or wrinkled skin, most visible when you bend or sit.
• Hollows at the sides of the hips, as fat loss reveals the shape of the pelvis underneath.

How noticeable it is varies enormously. Some people simply have a smaller, slightly softer bottom that few would call a problem. Others, usually after losing a very large amount of weight, are left with folds of skin that rub, sweat and are difficult to dress around, much like a saggy bum from any other cause.

What Is Mounjaro Bum?

Mounjaro bum is the same thing under a different name. Mounjaro (tirzepatide) acts on two gut hormone receptors rather than one, and on average it produces more weight loss than semaglutide. In the main trials, people lost an average of 14.9% of their body weight over 68 weeks on semaglutide^[1] and up to 20.9% over 72 weeks on the highest dose of tirzepatide^[2]. More weight loss means a greater chance of visible change to the buttocks, face and breasts. The facial version, Mounjaro face, works in exactly the same way.

Why Does Ozempic Cause a Flat, Saggy Bum?

Weight-loss injections do not target the buttocks. They reduce your appetite, so you eat less and lose weight, and the buttocks are one of the places that weight comes from. Three changes then combine to produce the look people call Ozempic butt.

1. Fat Loss From the Buttocks

The buttocks and hips hold a large share of the subcutaneous fat that sits under the skin, particularly in women. That fat gives the buttock its rounded projection. When it shrinks, the buttock gets smaller and flatter, and it can lose its shape as well, because fat does not always shrink evenly from every part of it.

2. Muscle Loss on Ozempic and Mounjaro

When you lose weight, you lose some lean tissue as well as fat. In the 2021 STEP 1 trial of semaglutide in the New England Journal of Medicine, a body-scan substudy found that roughly two-fifths of the weight lost was lean mass rather than fat^[1]. In the main tirzepatide trial the share was smaller, with about three-quarters of the weight lost coming from fat^[2].

Those figures sound alarming, but they need context. Lean mass includes water, organs and connective tissue as well as muscle, and a 2024 review found the proportion varies widely between studies, from 40% to 60% of the weight lost in some to around 15% or less in others. Scans that measure muscle directly suggest much of the change is in line with what you would expect for the amount of weight lost^[3]. Even so, the gluteal muscles are among the largest in the body and help give the buttock its shape, so any loss there shows. Older people, and anyone who does little resistance exercise, tend to lose proportionally more.

3. Skin That Cannot Shrink Back

Skin that has been stretched for years by extra weight does not always contract when the weight comes off. Skin samples from people who have lost large amounts of weight show damaged, disorganised collagen and elastic fibres^[4], and the skin’s ability to make new collagen falls naturally with age^[5]. When the fat underneath shrinks faster than the skin can follow, the skin hangs, and on the buttock it gathers at the bottom and pulls the crease lower. Our guide to loose skin vs fat explains how to tell which of the two you are looking at.

Is Ozempic Butt Caused by the Drug or the Weight Loss?

The evidence points to the weight loss. People have described the same change after bariatric surgery and large diet-led weight loss for decades. What the injections have changed is the scale and the speed: far more people are now losing enough weight, quickly enough, for the effect to show. There is no good evidence that semaglutide or tirzepatide damages the skin or buttock tissue directly.

Who Is Most Likely to Get Ozempic Butt?

Not everyone who loses weight on an injection ends up with a flat or saggy bottom. The risk is higher if:

• You lose a lot of weight. The more fat comes off, the bigger the change in shape and the more skin is left behind.
• You lose it quickly. Skin has less time to adapt, and losing a large amount of weight quickly tends to leave more loose skin than losing the same amount slowly.
• You are older. Skin elasticity and muscle mass both decline with age, so the same weight loss shows more at 55 than at 30.
• Your buttocks held a lot of fat. People who naturally carry weight on the hips and buttocks have more volume to lose there.
• You do little strength training. Without resistance exercise, a larger share of the weight you lose comes from muscle.
• Your weight has gone up and down before. Repeated stretching, including from pregnancy, leaves skin less able to recover.

How to Avoid Ozempic Butt

You cannot completely stop your buttocks getting smaller when you lose weight, and how much loose skin you are left with depends largely on your age, your genes and how much you lose. What you can do is protect the muscle underneath, and that makes a visible difference to shape.

Strength Training for Your Glutes

Resistance exercise is the most useful thing you can do. A meta-analysis of trials in older adults with obesity found that adding resistance training to a calorie-restricted diet prevented most of the muscle loss the diet alone caused^[6], and a 2026 analysis of 34 randomised trials found that exercise prevented nearly half of the lean mass lost during dieting, with strength or mixed training doing best^[7]. Two or three sessions a week that load the glutes progressively harder are enough to make a difference. Good exercises for Ozempic butt include:

• Hip thrusts and glute bridges
• Romanian deadlifts
• Bulgarian split squats and walking lunges
• Step-ups onto a box or bench
• Cable kickbacks and abduction work for the upper outer buttock

Squats help too, although they work the thighs as much as the glutes. Our article on BBL vs squats explains what exercise can and cannot change: it can build the muscle, but it cannot replace lost fat or tighten loose skin.

Eat Enough Protein

Appetite suppression makes it easy to under-eat protein. Higher-protein diets help preserve lean mass during weight loss: in a meta-analysis of 20 randomised trials in adults over 50, those getting at least 25% of their energy from protein, or about 1 g per kilogram of body weight a day, kept more lean mass and lost more fat^[8]. Ask your prescriber or a dietitian what target suits you.

Lose Weight at a Pace Your Body Can Keep Up With

Weight-loss injections are started at a low dose that is increased step by step, and some people do better staying on a lower dose for longer. Do not change your dose yourself, but if you are losing weight very quickly and noticing changes in your face or body, it is a reasonable conversation to have with your prescriber.

Plan for Stopping

If you stop the injection, much of the weight tends to come back. One year after stopping semaglutide in the STEP 1 trial, people had regained about two-thirds of the weight they had lost^[9]. Regained fat does not reliably return to the buttocks in the same shape, and skin that has loosened does not tighten again, so stopping is not a way to reverse Ozempic butt.

Could New Drugs Stop the Muscle Loss?

Several drugs designed to protect muscle during weight loss are being tested alongside weight-loss injections. The furthest along block the signals that limit muscle growth. In a 2026 meta-analysis of four trials, one of them, bimagrumab, increased lean mass by an average of 1.7 kg while reducing fat, although it also caused more muscle spasms and diarrhoea, and more people stopped taking it^[10]. None is licensed for this use in the UK, and none will replace fat that has already gone or tighten loose skin.

How to Fix Ozempic Butt: Treatments Compared

The right treatment depends on what has happened to your buttocks: lost volume, loose skin, lost muscle, or a mixture. That is the first thing your surgeon assesses at consultation, and it is why one person with Ozempic butt needs a BBL while another needs a lift.

Exercise for Mild Ozempic Butt

If your skin is still reasonably firm and you have mainly lost muscle tone, a structured glute programme may be all you need. Give it three to six months of consistent training before judging the result.

Non-Surgical Options: Morpheus8 and Buttock Filler

Morpheus8 combines microneedling with radiofrequency energy to tighten skin. Over a course of sessions it can improve mild crêpiness on the buttocks and thighs, but it cannot lift skin that has dropped or restore lost volume.

For modest volume loss, hyaluronic acid filler can add shape without surgery. At Centre for Surgery we use HYAcorp filler for the buttocks, a filler made for body contouring, rather than Sculptra or other collagen-stimulating injections. The result is visible straight away and the filler breaks down gradually over time, so it suits people who want a smaller, temporary change or who are not ready for surgery. Our page on the liquid BBL explains what filler can and cannot do compared with fat.

BBL (Fat Transfer) for Ozempic Butt

A Brazilian butt lift uses liposuction to take fat from areas such as the tummy, flanks or back, then injects it into the buttocks to rebuild volume and shape. It replaces the fat that weight loss took away, so it often gives the most natural-looking result for a flat bottom, and it slims the donor areas at the same time. It works best when the skin still has reasonable elasticity: fat can fill a deflated buttock, but it cannot lift a large amount of hanging skin.

BBL earned a reputation as a dangerous operation, because fat injected into or beneath the gluteal muscle can enter large veins and travel to the lungs. Practice changed after surgeons’ societies recommended keeping the fat in the layer above the muscle. A 2020 survey of members of the American and international aesthetic surgery societies in the Aesthetic Surgery Journal found that the reported death rate fell from about 1 in 3,448 to 1 in 14,952 once those recommendations were adopted^[11]. At Centre for Surgery, fat is placed only above the muscle, a technique called superficial gluteal lipofilling, in line with BAAPS guidance on gluteal fat grafting.

Buttock Lift

A buttock lift removes a band of loose skin and fat from the top of the buttocks and lifts what remains, through a scar across the lower back that underwear usually covers. It suits people whose buttocks have dropped but who still have reasonable volume. On its own, though, a lift can flatten the buttock: in a 2017 study of lower body lifts after weight loss, the small group who had no volume added lost almost 1 cm of buttock projection on average^[12]. That is why many people need a lift combined with fat transfer or their own tissue, and our guide to BBL vs buttock lift sets out how surgeons choose between them.

Lower Body Lift With Auto-Augmentation

After very large weight loss, loose skin rarely stops at the buttocks. A lower body lift removes a band of loose skin all the way around the waist, lifting the buttocks, hips, outer thighs and abdomen in one operation. The buttock can then be rebuilt using tissue that would otherwise be discarded. In a 2018 study of 280 lower body lifts in Plastic and Reconstructive Surgery, 85% of patients also had their buttocks augmented, most often with flaps of their own tissue, and adding the augmentation did not increase the complication rate^[13]. Flaps based on the gluteal blood vessels can be turned into the lower inner buttock to add projection and define the crease^[14], and some surgeons add liposuction and fat grafting in the same operation; in one series of 23 patients, satisfaction scores averaged 97.5 out of 100^[15]. Our article on the flap technique for buttock augmentation after weight loss explains how it works.

Buttock Implants

For very slim people with little fat to spare, silicone buttock implants are another way to add projection. In the 2018 study, implants were reserved for patients with minimal fat on the lower and upper back, the group with little or nothing to transfer^[13]. In a comparative study, implants added about 5 mm of projection after a lower body lift while flaps kept projection roughly unchanged, at the cost of more pain in the first two weeks^[12]. Implants carry their own risks, including infection, implant movement and a firmer feel, and your surgeon will go through these with you.

What If You Don’t Have Enough Fat for a BBL After Weight Loss?

This is the most common problem we see in people with Ozempic butt. Weight-loss injections take fat from everywhere, including the tummy, flanks and thighs that would normally supply a BBL. If you are now slim, there may not be enough fat to harvest for a large change. The options are:

• A smaller-volume fat transfer. A skinny BBL uses less fat, placed where it makes the most difference, such as the upper buttock and the hollows at the sides of the hips.
• Your own tissue. If you also have loose skin, a lower body lift with auto-augmentation can rebuild the buttock without needing spare fat.
• Implants or filler. Buttock implants add lasting volume without donor fat, and HYAcorp filler adds a smaller, temporary change.
• Waiting. Some people choose to wait until their weight settles at a level that leaves enough fat to work with.

Our guides to what happens if you don’t have enough fat for a BBL and whether you can be too slim for a Brazilian butt lift go into more detail.

Ozempic Butt Before and After

Photos labelled “Ozempic butt before and after” online often show a single dramatic case without saying what was done. The photos in this guide are real Centre for Surgery patients who had a BBL, not specifically patients who lost weight on injections, but they show what fat transfer can do for the flat, low buttock that defines Ozempic butt: more projection in the upper buttock, a shorter crease and a smoother curve from waist to hip. You can see more results in our BBL before and after gallery.

At your consultation, your surgeon will show you results from patients with a similar starting point to yours, so that you have a realistic idea of what your own result could look like.

When Can You Have Surgery After Ozempic or Mounjaro?

There are two questions here: how long to wait after losing weight, and what to do about the injection itself.

Wait Until Your Weight Is Stable

Operating while your weight is still changing risks a result that loosens or loses shape within months. Surgeons generally advise waiting until your weight has been stable for several months at a level you expect to keep, and longer after very large weight loss, so that your skin has finished settling and your surgeon can see exactly what needs correcting. If you plan to stop the injection, bear in mind that most people regain much of the weight afterwards^[9]. The best time for surgery is usually once you have reached a weight you can maintain, with a plan agreed with your prescriber.

Do You Need to Stop Ozempic or Mounjaro Before Surgery?

Not necessarily. These drugs slow the emptying of the stomach, which raises concern about stomach contents being inhaled during sedation or anaesthesia. Current UK guidance, a 2025 consensus statement from the Association of Anaesthetists, the Royal College of Anaesthetists, the Centre for Perioperative Care and diabetes and obesity specialists, is that patients taking these medications should generally continue them before planned surgery, have a full risk assessment, and have an anaesthetic plan designed to reduce the risk of aspiration, agreed through shared decision-making^[16]. At Centre for Surgery, your surgeon and anaesthetist will assess you and give you individual instructions, including how long to fast. Please do not stop or change your medication on your own before an operation.

Ozempic Body: Face, Breasts, Arms and Thighs

The buttocks are rarely the only area to change. “Ozempic body” is the catch-all name for the same effects elsewhere:

• Face: volume loss in the cheeks and temples and looser skin along the jaw, the change behind Ozempic face.
• Arms: loose skin on the upper arms, which may need an arm lift rather than liposuction; our guide to arm lift vs arm liposuction explains the difference.
• Thighs: loose skin on the inner thighs, covered in our guide to sagging thighs after weight loss.
• Hands: more visible veins and tendons as fat is lost from the backs of the hands, which hand rejuvenation can soften.
• Skin folds: chafing and rashes where loose skin rubs, explained in our guide to skin irritation after weight loss.

What Are Ozempic Breasts?

Ozempic breasts describes breasts that become smaller, emptier and lower after weight loss on injections. Breasts are partly made of fat, so they often shrink as weight comes off, and the skin may not shrink with them, leaving the breast deflated with the nipple pointing downwards. Treatment ranges from a breast lift to implants, or both, and our guide to sagging breasts after weight loss covers the options.

If several areas are affected, they can sometimes be treated together. Our post weight loss surgery page brings together the procedures for the body after major weight loss, including excess skin removal.

Frequently Asked Questions

Why Choose Centre for Surgery for Buttock Surgery After Weight Loss?

Every operation at Centre for Surgery is performed by a GMC-registered plastic surgeon, at our CQC-regulated hospital on Baker Street, rated Good overall by the CQC. Your surgeon will assess what has changed, the volume, the skin or the muscle, and recommend the treatment that fits, which may be simpler than the one you came in asking about. The surgeon who assesses you is the surgeon who performs your surgery, and we publish our clinical outcomes and patient safety data. Body contouring after major weight loss is worth doing well: a systematic review of quality-of-life studies found it improved physical, psychological and social wellbeing^[17].

Your initial consultation is £100, redeemable against the cost of your procedure if you go ahead. Finance is available for some procedures through Chrysalis Finance, subject to status, but not for BBL, buttock implants or a non-surgical butt lift. See our finance options page for details.

Phone: 020 7993 4849 | Address: 95–97 Baker Street, Marylebone, London W1U 6RN
Contact us to schedule a consultation

References

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14. Colwell AS, Borud LJ. Autologous gluteal augmentation after massive weight loss: aesthetic analysis and role of the superior gluteal artery perforator flap. Plastic and Reconstructive Surgery 2007;119(1):345–356. doi:10.1097/01.prs.0000244906.48448.5d
15. Alves HRN, Nicolas G. Gluteoplasty with lumbar gluteal flap associated with liposuction and fat grafting: a safe technique for massive weight loss patients. Aesthetic Surgery Journal 2024;44(4):404–411. doi:10.1093/asj/sjad339
16. El-Boghdadly K, Dhesi J, Fabb P, et al. Elective peri-operative management of adults taking glucagon-like peptide-1 receptor agonists, glucose-dependent insulinotropic peptide agonists and sodium-glucose cotransporter-2 inhibitors: a multidisciplinary consensus statement. Anaesthesia 2025;80(4):412–424. doi:10.1111/anae.16541
17. Toma T, Harling L, Athanasiou T, Darzi A, Ashrafian H. Does body contouring after bariatric weight loss enhance quality of life? A systematic review of QOL studies. Obesity Surgery 2018;28(10):3333–3341. doi:10.1007/s11695-018-3323-8