Study analysis · JHEP Reports · 2025

Losing weight with a drug might make you gain it back faster — here's why.

Both diet and a weight-loss drug shrink fatty liver the same amount, but stopping the drug triggers weird body signals that could make you regain weight.

Reading level
Low certainty
Level 1b · Individual RCT

Overview

What the study found

The study in plain English — the bottom line, every takeaway we extracted, and what to do with them.

In simple terms

This study is like a fair race between two ways to lose weight: eating less and taking a medicine. It shows that during the race, the medicine helped with blood sugar and fats more than just eating less. But once the race ended, the medicine group started having weird body changes that didn’t happen in the eating group. So we know what happened during the race, but we don’t know if one way is better overall.

What’s the bottom line?

Two ways to lose weight—eating less or taking a drug—both shrink fat in the liver equally. But the drug also helps blood sugar and fat production in the liver while you're taking it. When you stop the drug, those benefits vanish and your body sends out strange signals that might make you gain weight again.

How strong is this study?

This study tried to be fair by randomly picking who got which weight-loss method, which is good. But it only had 29 people, no one was blind to who got what, and it didn’t last long. So while we can trust what happened during the study, we can’t be super sure it would work the same for everyone or for a long time.

Reporting

40 / 100

  • COI disclosure+40/40
  • Data availabilitydata not shared
  • Code availabilitycode not shared
Methodology

60 / 100

  • Randomization+20/20
  • Blindingnot blinded
  • Control group+15/15
  • Sample size (n=29)+2.7/20
  • Follow-up+10/10
Publication

100 / 100

Statistical

77 / 100

  • P-values+15/15
  • Effect size+20/20
  • Confidence intervalsno confidence intervals
  • Pre-registration+15/15

Each component is scored out of 100 and then capped by the study design — a case series cannot reach the ceiling a randomised trial can, however well it is reported.

Where it sits

RCT reviews

Max 100

Randomized Trials

Max 90

Reviews of Cohort Studies

Max 85

Cohort Studies

Max 72

Reviews of Case-Control Studies

Max 63

Case-Control Studies

Max 58

Cross-Sectional & Case Series

Max 50

Expert Opinion

Max 5
StrongerWeaker
Randomized Trials
Level 1b
45

45 / 100

Probability of being correct

Participants are randomly assigned to treatment or control groups, minimizing bias. The gold standard for testing whether an intervention causes an effect.

This design can establish causation. Randomization allows causal inference for the comparison between GLP-1RA and lifestyle interventions during the 12-week treatment period. However, the small sample size (n=29), lack of blinding, and short duration limit confidence in long-term or population-level causal claims, especially regarding withdrawal effects.

Major COI

Major conflicts that significantly reduce study credibility

The study was funded by Novo Nordisk, the manufacturer of liraglutide, and the drug was provided by them, raising concerns about potential influence on study design and interpretation, despite no explicit funder control over analysis or publication.

Industry Funded
Funder Involved

Funders

Novo Nordisk

Conflict Details

multiple authors
Funding

Novo Nordisk: Provided liraglutide for the trial and sponsored the study.

The study was sponsored and monitored by the University of Oxford, but Novo Nordisk supplied the investigational drug. No independent data monitoring committee or third-party analysis is mentioned. The trial was registered as an Investigational Medicinal Product trial, indicating industry sponsorship. While authors are not stated to be employed by Novo Nordisk, the close alignment of study design with commercial interests (testing liraglutide vs. lifestyle) and lack of transparency on funder input beyond funding raises significant bias risk.

Key takeaways

  1. 01

    Both groups lost ~5 kg and reduced liver fat by 7.5%.

  2. 02

    The drug group had better blood sugar and lower liver fat production during treatment.

  3. 03

    After stopping, blood sugar worsened and 4 inflammatory proteins (MMP-10, IL10RB, FGF-23, Flt3L) rose only in the drug group.

  4. 04

    Yes—losing weight helps the liver no matter how you do it, but stopping the drug may trigger biological changes that make it harder to keep the weight off.

Surprising findings

  • Liraglutide improved glucose control and lowered liver fat production more than diet — but all benefits vanished after stopping, while diet’s effects persisted.Most assume drug effects are stronger and longer-lasting — but here, the drug’s advantages disappeared completely, while diet’s liver improvements stuck, even though participants likely continued some healthy habits.
  • Adipose tissue gene expression changed significantly after liraglutide withdrawal — but not after lifestyle withdrawal — despite identical weight loss.We expect lifestyle changes to cause lasting biological shifts — but this study shows the drug, not the diet, triggered unique gene dysregulation after stopping.

Practical takeaways

If you're using a GLP-1 drug for fatty liver or weight loss, plan for long-term maintenance before you stop — don’t assume the benefits will stick.

This study had only 29 participants and no placebo group; lifestyle participants may have continued healthy habits after withdrawal, which could skew results.

medium confidence

Prioritize sustainable lifestyle changes over short-term drug use — they produce equal liver benefits without the risk of post-treatment metabolic rebound.

Lifestyle changes are harder to maintain for many people — this doesn’t mean drugs are useless, just that they’re not a permanent fix.

medium confidence

Why this study matters

Same Weight Loss, Different Biology

Both liraglutide and lifestyle intervention led to identical weight loss (avg. ~5 kg) and reduced liver fat by 7.5%. But only liraglutide improved glucose tolerance and lowered liver fat production (DNL) during treatment — yet all benefits vanished after stopping.

It challenges the idea that drugs are 'better' than diet — showing that while drugs offer temporary metabolic perks, they don't outperform lifestyle changes in the long run and may even backfire.

The Hidden Warning Signs After Stopping the Drug

Twelve weeks after quitting liraglutide, four inflammatory proteins — MMP-10, IL10RB, FGF-23, and Flt3L — spiked in blood, and fat tissue genes became dysregulated. These changes didn’t occur after stopping dieting.

This suggests the drug doesn’t just help you lose weight — it may rewire your body in a way that makes rebound weight gain more likely, like a biological booby trap.

DNL Rebound: Fat Production Comes Back Hard

Hepatic de novo lipogenesis (DNL) — the liver’s process of making new fat — dropped during treatment in both groups, but rebounded after withdrawal in everyone. This means even diet-induced weight loss doesn’t permanently fix fat production.

It proves that weight loss alone doesn’t reprogram your liver — the body fights to restore fat storage, making long-term maintenance harder than we thought.

Want the whole report?

Detailed mode opens the full scientific breakdown — every score component, the methodology, conflicts of interest, the evidence analysis behind each claim, and the raw study data.

Standing

Who’s using this study?

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1 video from Physionic cite this study, drawing 1 claim from it.

All 1 video reference this study through extracted claims.

Authored by

15 researchers

If this is your work, this is how we attribute it on Fit Body Science. Ahmad Moolla is listed as the lead author.