Composa
What it measuresLog in
Measured, not guessed

The scale can't tell you what you're losing.

On GLP-1 medication or a peptide, a meaningful share of what comes off is muscle rather than fat — and the number on the scale looks identical either way. Composa measures the difference every week, from your own readings and a tape measure, and tells you honestly when it cannot.

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Core measurement is free, with no paywall on day one. Paid human services are separate and optional.

What Composa measures

Fat, or the muscle underneath itA weekly split of what the change is actually made of, from your weight and a tape measure. No scan to book, no smart scale, nothing bought.
Muscle ReserveOne number for how much of your lean mass you are holding on to — the thing that decides whether the weight stays off when the prescription stops.
A protein target and a calorie floorBoth derived from your own body, not a generic plan. On a suppressed appetite, eating too little is the fastest way to lose muscle instead of fat.
Any medication, or any peptideLog what you actually take — dose, date, site — whether or not it is one of the three names everyone knows. Composa is not built around one drug.
The transition, not just the lossTrials show roughly two-thirds of lost weight returns within a year of stopping. Composa keeps measuring through the part most tools treat as the end.
Real people, when you want themPaid coaching is a named human reading your weeks and writing back. There is no AI pretending to be your coach, here or anywhere in the product.
The whole arc, not just the losing part
TrackUnderstandCoachingTransitionMaintainBuild

Most tools stop at the number going down. The part that decides whether any of it lasts is what happens around and after the prescription — so measurement, the transition and maintenance are all the same product rather than an upsell.

What Composa refuses to do
Start measuring

You need a tape measure and your weight. Everything else Composa derives from what you log, and it will tell you which weeks it could measure and which it could only estimate.

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