What happens when you stop a GLP-1
Qué pasa cuando se suspende un GLP-1
Illustrative image. Does not represent guaranteed results.
In the STEP 1 trial extension, published in Diabetes, Obesity and Metabolism, 327 participants stopped receiving semaglutide after 68 weeks. One year later they had regained 11.6 of the 17.3 percentage points of weight they had lost. Two-thirds.
This is probably the most uncomfortable number in the entire field, and also the most important. Almost nobody puts it at the front of the conversation. We do, because it completely changes how you should think about starting.
Key points
- In the STEP 1 extension, one year after stopping, participants had regained two-thirds of the weight they lost.
- The cardiometabolic improvements gained during treatment also reverted toward baseline.
- In SURMOUNT-4, those switched to placebo gained 14.0% over 52 weeks; those who continued tirzepatide lost a further 5.5%.
- In that same trial, 89.5% of those who continued maintained at least 80% of their loss, versus 16.6% of those who stopped.
- The STEP 1 authors concluded the findings confirm the chronicity of obesity and suggest ongoing treatment is required.
In this article
The STEP 1 numbers, in full
The original trial followed 1,961 adults for 68 weeks. The extension took a representative subgroup of 327 people who had completed treatment and followed them a further year, with no medication and without the study lifestyle intervention.
| Period | Weight change |
|---|---|
| Week 0 → 68 (on semaglutide) | −17.3% |
| Week 68 → 120 (off treatment) | +11.6 points |
| Net, week 0 → 120 | −5.6% |
Look at that last row: the net balance is still negative. After a full year with no medication, the group remained 5.6% below starting weight, versus 0.1% for placebo. Not everything was lost. But most of it was.
What also reverted
The authors report that the cardiometabolic improvements seen through week 68 returned toward baseline for most variables. In other words: not just the weight.
SURMOUNT-4: the same experiment, in reverse
SURMOUNT-4, published in JAMA, asked the question from the other direction. It first gave tirzepatide to 783 adults for 36 weeks — they achieved a mean 20.9% reduction — then randomized 670 of them: half continued the medication, half switched to placebo.
| Week 36 → 88 | Weight change |
|---|---|
| Continued tirzepatide | −5.5% further |
| Switched to placebo | +14.0% |
And the most telling figure: 89.5% of those who continued maintained at least 80% of what they had lost. Among those who stopped, only 16.6%.
Two independent trials, two different medications, the same conclusion.
What this means in practice
It means these medications behave like treatment for a chronic condition, not like a course of antibiotics. The STEP 1 authors say it plainly: the findings confirm the chronicity of obesity and suggest ongoing treatment is required to maintain improvements.
The question worth asking before starting
It is not "how much will I lose?" It is "what happens in two years?" If the honest answer is that you cannot sustain it, that is useful information now, not eight months from now.
Where follow-up fits
A supervised plan includes periodic check-ins reviewing how you are doing, whether the dose is still right, and what is happening with your muscle mass, your eating and your labs. That does not erase what the trials show — but it does keep the decision to stop from happening by accident, with no plan.
What nobody has measured yet
Let us be precise about the limits of the evidence. The STEP 1 extension was explicitly exploratory and analyzed a subgroup of 327 people, not the original 1,961. And both studies measured abrupt discontinuation.
What we do not know from published data of this quality: whether gradual dose reduction changes the outcome, or whether a structured maintenance program alters that curve. It is being studied. It is not settled.
Who is this NOT for?
If you are looking for a short course with a permanent result, the evidence says that does not exist here. We would rather tell you before you spend your money.
If your financial situation does not allow sustaining treatment beyond a few months, that is worth raising with the clinician from the start. Some conversations are better had at the beginning.
And if you are hoping to avoid changes in eating and movement, note that in both trials the medication was studied alongside a lifestyle intervention — never instead of one.
Frequently asked questions
So is this forever?
Published evidence indicates that maintaining the effect depends on continued treatment. How long that means in your case is a clinical decision a licensed provider makes with you, reviewing your full situation.
If I stop, do I go right back to where I started?
Not necessarily. In STEP 1, one year after stopping the group remained 5.6% below starting weight. Most was regained, not all. Individual results vary and are not guaranteed.
Does tapering the dose help?
There is no published data of STEP 1 or SURMOUNT-4 quality answering that. Both trials measured discontinuation, not tapering. Anyone assuring you otherwise is going beyond the evidence.
Why tell me this if you sell the program?
Because if you start without knowing, you will find out anyway — and worse. We would rather you decide with the full picture, even when that means deciding no.
Do exercise and protein change anything?
In both trials the medication was studied as an adjunct to a lifestyle intervention. Preserving muscle mass during weight loss is a reasonable clinical goal — we cover it in protein and muscle.
How often are check-ins?
It depends on the plan the clinician determines. A supervised program includes periodic follow-up reviewing dose, tolerance and labs.
Do you offer support in Spanish?
Yes. All of our content and support is available in Spanish.
Sources
- Wilding JPH, et al. Weight regain and cardiometabolic effects after withdrawal of semaglutide: the STEP 1 trial extension. Diabetes Obes Metab. 2022;24(8):1553-1564. — DOI
- Aronne LJ, et al. Continued Treatment With Tirzepatide for Maintenance of Weight Reduction (SURMOUNT-4). JAMA. 2024;331(1):38-48. — DOI
- Wilding JPH, et al. Once-Weekly Semaglutide in Adults with Overweight or Obesity (STEP 1). N Engl J Med. 2021;384(11):989-1002. — DOI
- Jastreboff AM, et al. Tirzepatide Once Weekly for the Treatment of Obesity (SURMOUNT-1). N Engl J Med. 2022;387(3):205-216. — DOI
This article is informational and is not medical advice. SCTS1 does not prescribe medication. All medical care, prescriptions, and treatment plans are provided by licensed healthcare providers through our partner platform. Treatment eligibility is determined by a licensed provider. Compounded medications contain the same active ingredient class but are not FDA-approved finished pharmaceuticals. Individual results vary and are not guaranteed.