Medicated weight loss plateaus explained
Reviewed by Sheena Bagga
If you’re asking yourself, “Why am I not losing weight anymore?”, you're not alone. One of the most frustrating parts of a weight loss journey is when you get to a point where your progress slows down or stops completely, even though you're still putting in the work. This is called a weight loss plateau, and it's very common, many people experience it.
Whether you’re trying out a new diet, exercising daily or using weight loss medications like Mounjaro, Wegovy, or Saxenda, it's completely normal to go through a period where you're losing weight, followed by a plateau.
Quick summary
- A weight loss plateau is when your progress slows or stops, even though you're still following your plan
- You can still experience a weight loss plateau if you're on a treatment like Mounjaro
- You can get past a weight loss plateau with a few tweaks to your routine, a dose review and support from your healthcare team
If you're wondering, "Why has my weight loss stalled?" or "Why has my weight loss plateaued even though I’m doing everything right?", this article is here to help.
What is a weight loss plateau?
A weight loss plateau is when your weight stays the same for a few weeks or more, even though you’re still eating well, moving more, or taking weight loss medication. Many people experience this kind of weight slump or weight loss slowdown, and it can happen at any point in your journey.
This can feel discouraging, especially when you're thinking, “Why am I not losing weight while dieting and exercising?” or “I’m in a calorie deficit but not losing weight, why?” These are common questions, and the answer is often that your body has hit a natural pause point.
About 85% of people who try to lose weight experience a plateau during weight loss. It’s your body’s way of trying to adjust and protect itself. After all, weight loss affects your metabolism, hormones, and energy uses, so your body may try to slow things down to “hold on” to what it has.
Hitting a plateau doesn't mean it's the end of your progress. It just means your body needs a little time, or a few small tweaks, to get things moving again.
The difference between a weight loss plateau and normal fluctuations
It’s easy to confuse a weight plateau with normal weight fluctuations.
However, a true plateau in weight loss is different from everyday ups and downs. If your weight hasn’t changed despite consistent effort, you’re likely dealing with a real plateau.
If you’re thinking, “How many weeks is considered a weight loss plateau?”, it’s generally around three weeks or more with no progress.
Why does a weight loss plateau happen?
If you're wondering, “Why has my weight loss stopped?” or “Why can’t I lose weight even though I’m trying?”, know that this is a normal part of the process. Whether your weight loss has stalled on Mounjaro or you’re working with just diet and exercise, your body can slow things down for several reasons.
"A plateau doesn’t mean you’ve failed or that your body’s stuck forever. It’s just a natural pause, and with the right changes, you can get moving again.” - Sheena Bagga, Pharmacist
The good news is, a weight loss plateau often goes away on its own with a few smart tweaks. But understanding why it happens is the first step to overcoming it.
Slowing and adapting metabolism
As you lose weight, your body naturally needs fewer calories, which means your metabolism, how quickly you burn energy, might slow down a little. Don't worry, though! This is completely normal and just shows how well your body works to keep everything balanced.
This process is called metabolic adaptation, and it’s your body’s way of adjusting to changes. While it might make losing more weight a bit tricky, it definitely doesn’t mean you can't keep going! It just means you may need to switch things up a bit and find a new approach that works for you.
Diet changes and your body’s set-point
Sometimes, even when you’re eating well, your calorie needs may change as you lose weight. What worked when you first started might not be quite enough to keep the scale moving now.
There’s also something called the set-point theory. Some experts believe that your body has a certain weight range it tries to stay within. If you dip below that range, your body might try to bring you back by making you feel hungrier or slowing down how fast you burn energy.
Not everyone agrees with this theory, but it helps explain why your weight might settle or bounce back a little at times, even if your habits haven’t changed.
Think about when you gain a bit of weight over the holidays and then go back to your normal routine. Your body usually returns to its usual weight without much effort. Or if you’ve been sick and lost weight, you might notice your appetite comes roaring back as your body works to rebuild.
It’s your body’s way of finding its “comfort zone.” But that doesn’t mean you can’t shift that zone over time with the right support.
Hormonal changes
As you get closer to your weight loss goal, you might start to feel a little hungrier, even though you’re still taking your medication. This can be confusing and leave you wondering, “Why am I not losing weight on Mounjaro anymore?”
Over time, your body can start to adjust to the effects of weight loss medications like Mounjaro, Wegovy, or Saxenda. These are designed to reduce your appetite and help regulate your hunger signals. But eventually, your body will build a tolerance to the medication: meaning you don’t feel as full, or hunger comes back more strongly (this is why the doses of treatments like Mounjaro or Wegovy are increased over time).
This change can lead to eating slightly more without realising it, and that alone might be enough to slow weight loss or lead to a Mounjaro weight loss plateau. If you’re thinking, “Why has my weight loss plateaued while on medication?”, this could be the reason.
Can medicated weight loss treatments stop working?
If it feels like your medication has stopped helping you lose weight, you’re not alone. You’re still eating well, moving your body, and taking your prescription, but the scale hasn’t moved in weeks. You might even be thinking, “Why am I not losing weight while dieting and exercising?”
This can feel frustrating, as if you’ve hit a wall or that your medication has stopped working. But it doesn’t mean the treatment has failed. It often means your body has adjusted to the current dose, and it’s time to check in with your doctor.
“It’s not unusual for people to hit a pause in their weight loss. It doesn’t mean you’re doing anything wrong. Often, a small change like adjusting the dose can help you get going again.” - Sheena Bagga, Pharmacist
If your weight loss has stalled for a few weeks, don’t panic. This is common, and there are things you can do to get back on track.
How to break through a weight loss plateau
If your weight hasn’t changed for a while despite making healthy lifestyle changes, you might be experiencing a real plateau during weight loss. The good news is that it’s usually temporary, and there are a few ways to get things moving again.
Review your treatment dose
A common reason for a medicated weight loss plateau is that the dose you’re on isn’t quite enough anymore. Most GLP-1 medications (like Mounjaro) are prescribed in stages starting low and slowly increasing. This helps avoid side effects and gives your body time to adjust.
If you’ve stayed on the same dose and you're stuck at the same weight, it might be time to talk to your doctor about whether it’s time to move to the next dose.
“We often see that after the early stages of weight loss, people need a slightly higher dose to keep seeing results. But this should always be done safely and under guidance." - Sheena Bagga, Pharmacist
Don't try to change your dose yourself, your healthcare provider can help you decide if an adjustment is the right move.
Review and adjust your diet
Sometimes a small increase in calories can creep in without us realising, especially when appetite starts to return. It’s worth checking in with your meals and snacks. You might still be in a calorie deficit, but not enough to continue seeing weight loss.
If you're wondering, “Why can’t I lose weight even though I’m eating well?”, it might be time to reassess portion sizes or the balance of nutrients in your meals. A dietitian or clinician can help with this.
Review and adjust your exercise routine
If you’ve been doing the same workouts for a while, your body may have adapted. That’s normal! To break a weight plateau, try switching things up. Adding strength or resistance training can help you build muscle, which burns more calories at rest. If you’re exercising but not losing weight, it might not mean you’re doing anything wrong, it could just be time for a new challenge.
Ensure you're getting enough sleep
Not getting enough sleep can affect your hormones, energy, and hunger levels, which might make it harder to stay on track. If your weight loss has stalled, ask yourself if you're getting the rest your body needs.
Aim for 7–9 hours of quality sleep each night and try to keep a consistent bedtime routine where possible.
Manage stress levels
Stress plays a big role in your weight. It can affect your appetite, make you crave certain foods, or reduce your motivation to stay active. If you’re in a weight loss slump, stress might be part of the reason.
Long-term stress can make your body hold onto weight. If stress is affecting your daily life, talk to your GP. They might recommend support like counselling, CBT (cognitive behavioural therapy), or even suggest hobbies that can help you relax.
Even small steps, like going for a walk, journaling, or setting aside time to unwind, can help you get through a plateau in weight loss.
How long does a weight plateau last?
This is a common question: “How long can a weight loss plateau last?”
The answer is, it depends. For some people, a plateau may last a few weeks, for others it could go on for a couple of months. But the important thing to know is that it’s usually temporary. Your body is just adjusting. With the right support and small changes, most people are able to get past a weight loss plateau and continue seeing progress.
When to seek medical advice
If you’ve been stuck in a weight loss plateau for more than 4–6 weeks, or if you're feeling unsure about your medication dose, it’s a good idea to talk to a healthcare professional. This is important if you notice new side effects or wondering if your Mounjaro is not working anymore.
“If your weight loss has stopped and you’re unsure what to do next, don’t struggle alone. Your clinician can help you review your medication, your lifestyle, and decide on the next step that’s right for you” - Sheena Bagga, Pharmacist
Sometimes all it takes is a fresh look at your plan to get things moving again.
References
https://www.ncbi.nlm.nih.gov/books/NBK576400/
https://eating-disorders.org.uk/information/the-psychology-of-dieting/
https://www.henryford.com/blog/2021/04/daily-weight-change-explained
https://pmc.ncbi.nlm.nih.gov/articles/PMC12096058/
https://www.theindependentpharmacy.co.uk/weight-loss/guides/breaking-through-weight-loss-plateaus-on-mounjaro-and-wegovy
https://www.mayoclinic.org/healthy-lifestyle/weight-loss/in-depth/weight-loss-plateau/art-20044615
