You may have lost significant weight on Wegovy, Ozempic, or Mounjaro — and now you're wondering whether you can stop. Or perhaps you need to stop due to cost, availability, or side effects. It's one of the most common questions among people on GLP-1 treatment: What happens to my weight and health when I stop? Here's what the research actually shows.

Your body remembers its old weight

GLP-1 medications work by suppressing hunger signals and raising the biological threshold for feeling full. As long as you take the medication, your body is in an altered state. When you stop, these signals gradually return to baseline — and for many people, that means hunger comes back and weight goes up again.

This is not a sign of weak willpower. It's biology. Obesity is a chronic condition driven by powerful hormonal mechanisms, and GLP-1 medications treat those mechanisms — but don't cure them permanently. Just as blood pressure medication keeps blood pressure down while you take it, GLP-1 medication keeps weight down while you take it.

What the STEP 1 extension study tells us about semaglutide

The most cited study in this area is the extension study to the STEP 1 trial, published in Diabetes, Obesity and Metabolism in 2022. Participants had used semaglutide 2.4 mg (Wegovy) for 68 weeks, losing an average of 17.3% of their body weight. They then stopped the medication and were followed for another 52 weeks.

The result was clear: within one year of stopping, participants had regained two-thirds of the weight they had lost. By week 120 (one year after stopping), the average net weight reduction was only 5.6% — compared to the 17.3% achieved during treatment. The weight did not return entirely to baseline — but most of it did.

What the SURMOUNT-4 trial tells us about tirzepatide

For tirzepatide (Mounjaro), the SURMOUNT-4 trial (published in JAMA, 2023) is the most informative study. Participants received tirzepatide for 36 weeks and lost significant weight, after which half continued the medication and half switched to placebo for 52 weeks.

Of those who stopped tirzepatide, 82.5% regained at least 25% of their lost weight within one year. By comparison, the group that continued tirzepatide lost a further 5.5% during the same period. The difference was dramatic: continued treatment versus stopping produced very different outcomes.

A follow-up analysis also showed that participants who regained the most weight also experienced the greatest reversal of the cardiovascular benefits the medication had provided — including improvements in blood pressure, cholesterol, and blood sugar.

Does it always go wrong when you stop?

Not necessarily. A large real-world study from EPIC Research (2024) followed thousands of patients who stopped semaglutide or liraglutide and found that:

This shows that outcomes are highly individual. Factors like dietary changes, exercise habits, sleep quality, and stress levels all play a role in whether weight stays off after stopping.

What happens to your health beyond weight?

GLP-1 medications don't only cause weight loss — they also improve blood pressure, blood sugar, cholesterol, and other markers of cardiovascular health. These improvements are not permanent. Research shows that most of these health markers gradually return toward baseline as weight is regained.

For patients with prediabetes, this is particularly important: studies show that many who stopped semaglutide had reverted to prediabetic status one year after stopping — even though their blood sugar had normalised during treatment.

Weight regain is faster than after a diet

A new study from the University of Oxford (January 2026) compared weight regain after stopping medication versus stopping a diet programme. The conclusion was that weight returned faster after stopping medication — approximately 0.3 kg per month faster than stopping a dietary programme. This underscores that the medication actively suppresses the biological mechanisms driving weight gain, and these mechanisms are ready to reassert themselves as soon as the medication is gone.

When does it make sense to stop?

There can be good reasons to stop GLP-1 medication:

Always talk to your doctor before stopping treatment. A gradual taper may in some cases allow for a smoother transition than an abrupt stop — though research in this area is still limited.

What can you do to preserve your weight loss?

If you stop or plan to stop, there are things that can help you maintain some of your weight loss:

Is GLP-1 medication a lifelong treatment?

For many patients, the answer appears to be yes — just as is the case with medication for high blood pressure or high cholesterol. Obesity is a chronic disease, and for many people it requires chronic treatment. That doesn't mean everyone needs to take the medication forever, but it does mean that continuing long-term treatment is a realistic and legitimate option if it is possible and appropriate.

This is an important conversation to have with your doctor — not a decision that should be made alone.

Summary

Sources