Two weeks is not a plateau
Body weight moves several hundred grams a day for reasons that have nothing to do with fat. Water retention, glycogen, salt, hormonal cycle, what is currently in your digestive tract, how warm it was, whether you slept. On a slow downward trend, that daily noise is comfortably larger than the signal.
The consequence is arithmetic rather than opinion: a fortnight of flat readings is completely compatible with a trend that has not changed at all. If you are losing around half a kilo a week and the day-to-day noise is a kilo, you will see stalls of one to three weeks routinely, forever, while still losing weight.
- Two weeks flat: noise. Keep going, keep logging, do not change anything.
- Four weeks flat: possibly noise, possibly the start of something. Worth watching, not worth acting on.
- Six to eight weeks with no downward trend: a real plateau, and worth working out why.
The three real reasons a trend flattens
When it is genuine, it is usually one of three things, and they have different answers.
The dose has settled and the effect with it
The level reaches a plateau four to five weeks after any increase. If the appetite effect has faded as that plateau was reached, the dose is doing what it does and the question is whether the ladder has further to go. That is a prescriber conversation.
Intake has quietly crept back
As side effects settle and the food noise becomes manageable, eating usually rises without any decision being made. This is the most common cause and the least visible one, because nobody notices a gradual change in their own behaviour.
A smaller body needs less
The same intake that produced a deficit at the start does not produce one twenty kilos later. This is not a failure of the medication; it is the arithmetic changing underneath a habit that did not.
There is a fourth possibility worth naming: nothing is wrong. Weight loss is not required to be linear, and a body that holds still for two months and then resumes is a normal thing that happens. Acting on every stall is how people end up climbing a dose ladder faster than their tolerance justifies.
What your log should show
A plateau conversation goes very differently when there is a record behind it. These are the five things worth being able to look up.
- The trend, not the readings. A line through a scatter of daily weights, over months.
- The dose history laid against it. When did each step start? Did the flattening begin four weeks after a step, or three weeks before it?
- Adherence. Late doses, missed doses and the drift you did not think mattered. A trend that flattens after a run of late shots is a different problem.
- Appetite and food noise scores. Whether the effect has genuinely faded or your intake changed while the effect held. These are opposite problems.
- Body composition, not just mass. Waist and lean mass moving while weight sits still is a real result that a scale alone reports as failure.
That last one matters more than it gets credit for. Weight is one number and a poor summary of what is happening. A stable weight with a falling waist measurement is progress; a stable weight with falling lean mass is a problem worth raising. The scale cannot tell those apart.
The trap of chasing it with dose
The instinct at a stall is to go up. Sometimes that is right and it is what the ladder is for. Two things are worth holding on to first.
A dose increase takes four to five weeks to reach its own plateau, so it is not a test you can run in a fortnight. And the increase restarts the side-effect adjustment window, so the first two weeks afterwards will feel like something is happening whether or not the trend eventually changes. The combination makes it very easy to conclude that a step worked when what you actually observed was a fortnight of eating less because you felt unwell.
A record of the previous steps – how long each took to show a change, what the trend did four weeks in – is the only thing that turns that into a real comparison. See dose schedules and titration.
The things that are not the dose
- Protein. Under-eating protein during rapid loss costs lean mass, which lowers what you burn and makes the next phase harder.
- Fluid. Dehydration is common when appetite is suppressed, and it shows on a scale in both directions unpredictably.
- Sleep. Poor sleep raises appetite and lowers adherence to everything else.
- Constipation. A genuinely stalled scale for a week is sometimes exactly what it looks like.
- Resistance training. Keeping muscle during a deficit changes the composition of the loss even when the total does not move.
None of these is advice from an app, and none of them replaces a clinician. They are on the list because they are the things a log makes visible and memory does not.
How Penwise handles it
Weight, body fat, lean mass, waist and resting heart rate sit on the same timeline as every dose, with a goal weight and progress against it. A scale on Apple Health or Health Connect feeds it automatically, so weighing often costs nothing in effort.
The Insights tab reports milestones as a share of where you started, and reports adherence drift when it is real. It says nothing when the evidence is thin, which at a plateau is the most valuable behaviour an app can have: the last thing anyone needs at week five of a stall is an algorithm inventing an encouraging pattern out of noise.
See the trend, not the reading
Weight, composition and dose history on one timeline. Free core tracker, no account, nothing sent anywhere.
Common questions
How long is a normal weight loss stall on a GLP-1?
Why has my weight stopped dropping on Mounjaro or Wegovy?
Should I increase my dose at a plateau?
Can I be losing fat while the scale does not move?
Does a plateau mean the medication stopped working?
How often should I weigh myself?
Sources
Every factual claim on this page traces to the product information a regulator publishes, or to a published trial. Links open on the site of whoever issued the document.
- Tirzepatide Once Weekly for the Treatment of Obesity (SURMOUNT-1) New England Journal of Medicine, 2022
- Once-Weekly Semaglutide in Adults with Overweight or Obesity (STEP 1) New England Journal of Medicine, 2021
- Continued Treatment With Tirzepatide for Maintenance of Weight Reduction (SURMOUNT-4) JAMA, 2024
Penwise is a tracking and education tool, not a medical device. Nothing on this page is medical advice, a diagnosis or a recommendation to start, stop or change a dose. Dosing decisions belong to you and your clinician. Ozempic, Wegovy, Rybelsus, Saxenda and Victoza are trademarks of Novo Nordisk; Mounjaro, Zepbound and Trulicity are trademarks of Eli Lilly. Penwise is not affiliated with, endorsed by or connected to either company.