Stated plainly: oral semaglutide · SOUL.
The figures are clear enough; the question is what they mean and what they do not.
I can supply the numbers if the specifics change the answer.
How should I read this, and where are the traps?
The relevant confounder is glycogen: each gram of stored glycogen carries about three grams of water, and both register as lean mass.
A deficit of five hundred to seven hundred and fifty kilocalories per day is the range within which lean preservation is generally achievable. Larger deficits work faster and cost more lean tissue per kilogram lost.
Resistance training two to four times weekly with progressive load is the intervention with the strongest evidence for reducing the lean fraction of loss. Cardiovascular exercise does not substitute for it on this endpoint.
Protein intakes in the 1.6 to 2.2 g/kg range are supported by meta-analyses of resistance-training studies for lean-mass retention in energy deficit.
Nothing here is medical or dietetic advice, and anyone with kidney disease has a protein question that needs a clinician.
Do not read the first fortnight as tissue loss. It is mostly glycogen and its water.
HPLC purity, identity confirmation and quantified content on the vial you actually hold. Reports arrive with the chromatogram attached, not just a number.
Submit a sampleFounded 1998. ISO 9001 and cGMP certified, 1,500+ staff and 200+ patents. The synthesis house behind a great many of the vials that get sent out for testing - batch-specific documentation with every order.
Visit GL BiochemAnswering this needs the rate of loss, because faster loss reliably costs a larger lean fraction.
Scan-to-scan precision on lean mass is around one to two per cent for a good DXA under standardised conditions, so a change of half a kilogram is inside the noise.
In practice, bone mineral density is measured on the same scan and falls slowly with weight loss; it is worth tracking on the same series rather than as a separate exercise.
The twenty-five per cent figure for lean loss in unstructured weight reduction is a long-standing result from body-composition studies across many interventions, including surgery.
Track absolute lean mass, not lean percentage, or the arithmetic will mislead you.
Answer first: lean mass falls during any substantial weight loss, typically as twenty to thirty per cent of the total, and the levers that change that fraction are protein intake and resistance training rather than anything pharmacological.
Glycogen depletion in the first fortnight releases the water bound to it — roughly three grams of water per gram of glycogen — which shows up as several kilograms of "lean mass" lost before any tissue has gone anywhere.
A daily protein intake in the range of 1.6 to 2.4 grams per kilogram of reference body weight is the range the resistance-training literature supports for lean-mass preservation in a deficit. At the top of that range the marginal return is small.
Comparing scans from different machines is not a comparison. Different manufacturers use different algorithms.
Protein and progressive resistance training. Those are the two levers; everything else is a detail.
It helps to be literal here: this is measurable rather than arguable, provided you use the same instrument under the same conditions each time.
Because appetite is suppressed in this class, protein intake tends to fall in absolute terms even when it rises as a percentage of a smaller intake. That is the specific mechanism by which lean loss gets worse here.
Trials in this class that measured body composition report lean fractions broadly consistent with other weight-loss interventions of similar magnitude.
Same machine, same time of day, same hydration state, or the series is noise.
edited 26 Jun 2025 by amara_nwachukwu — tightened the wording; no substantive change
In practice, preserving lean mass and gaining it are different objectives with different requirements, and in an energy deficit only the first is realistic for most people.
The conventional figure is that lean tissue accounts for roughly a quarter of total weight lost in unstructured weight loss, falling towards ten to fifteen per cent with adequate protein and progressive resistance training, and rising above a third with very rapid loss and no training stimulus.
Glycogen's water-binding ratio of roughly three to one is basic physiology and explains most early rapid weight change in any deficit.
Research-use compounds are not approved for human use, and body-composition planning does not change that.
A quarter is typical. Below a fifth is a good outcome. Above a third means slow down.
Ask PeptideStack is a static archive. Posting is closed, but the norms are worth stating: answer the question that was asked, show your working, cite the trial or the certificate, and say plainly where the evidence runs out.