Can you still gain weight on GLP-1 medications? Yes, and here's why

What's this video probably claiming?

Based on the caption alone, @caleysvensson appears to be sharing a personal or observed experience where weight gain occurred despite being on a GLP-1 receptor agonist. This is a genuinely important topic that gets buried under the avalanche of before-and-after content dominating the GLP-1 space. The creator is likely pushing back on the widespread assumption that these drugs are a guaranteed one-way ticket to weight loss. That framing is worth taking seriously. GLP-1s do not override physiology entirely, and the community rarely talks about the ceiling effects, the plateau problem, or the specific scenarios where the scale actually moves in the wrong direction. Whether this is anecdote, warning, or something more specific will require the actual transcript to confirm.

What does the science actually show?

The clinical trial data on GLP-1 agonists is genuinely impressive but comes with important caveats. The STEP 1 trial (Wilding et al., 2021, NEJM) showed semaglutide 2.4mg weekly produced a mean 14.9% body weight reduction over 68 weeks in adults without diabetes. The SURMOUNT-1 trial (Jastreboff et al., 2022, NEJM) showed tirzepatide 15mg produced up to 22.5% weight reduction. Those are averages. The distribution matters. In STEP 1, roughly 69% of participants achieved 10% or more weight loss, which means about 31% did not. Some patients plateau early, some lose modest amounts, and a subset experience weight gain during treatment due to factors including dose interruptions, insulin resistance, or compensatory eating behaviors that the drug does not fully suppress. The biology is more complicated than the marketing.

Where does the social media noise diverge from clinical reality?

The GLP-1 content ecosystem has a severe survivorship bias problem. The creators with dramatic transformations get the views. The people who gained three pounds on month two do not trend. This creates a distorted picture of what these medications reliably do for everyone. A few specific mechanisms actually do cause weight gain on GLP-1s that never get discussed. First, dose reductions due to gastrointestinal side effects reduce appetite suppression, potentially allowing caloric rebound. Second, muscle loss during rapid weight loss can lower resting metabolic rate over time, a phenomenon documented in the STEP trials where lean mass losses were proportionally significant. Third, psychological factors including stress eating and binge episodes can override even strong appetite suppression. None of this means the drugs do not work. It means the social media version of how they work is incomplete at best.

What should you actually know?

If you are on a GLP-1 and gaining weight, or not losing as expected, you are not broken and the drug is not necessarily failing. There are documented, biologically coherent reasons this happens. The SCALE Obesity and Prediabetes trial (Pi-Sunyer et al., 2015, NEJM) with liraglutide 3mg showed meaningful inter-individual variability in response, reminding us that population averages obscure a wide range of outcomes. Protein intake and resistance training during GLP-1 therapy appear to influence whether weight loss comes from fat or muscle, which affects longer-term metabolic outcomes. Additionally, stopping these medications even briefly causes rapid weight regain in most patients, as shown in the STEP 1 extension data. The takeaway is not that GLP-1s are overrated. It is that they are tools with specific use conditions, and content that frames them as foolproof is doing real patients a disservice.