Good morning.
A study presented at the Endocrine Society's June meeting did something most GLP-1 research skips. Instead of watching the scale, it watched people move, using Fitbit data from before and after they started the medication. What it found is the quiet part of the weight-loss story, and it's worth a few minutes this Saturday.
The number under the number
The researchers followed 753 adults on GLP-1 medications, most of them women, average age 52. After starting treatment, daily steps fell from about 5,050 to 4,490, and moderate-to-vigorous activity dropped from 27.9 minutes a day to 22.2. Nobody moved more once the weight came off. If anything, they moved less.
This was presented at a conference and hasn't cleared peer review yet, so treat it as an early signal, not a settled result. But the reason it matters is simple arithmetic. Weight lost on a GLP-1 isn't purely fat. A real share of it is lean muscle, and muscle is kept by using it. Lose weight and move less at the same time, and you can take off more muscle than you meant to. Heading into and through perimenopause, when muscle and bone are already harder to hold, that's a setup worth seeing coming.
The scale can be dropping while the exact thing you want to keep goes with it.
What the market's doing about it
We watch the search traffic shift with the science. The growth-hormone-axis peptides people ask us about, ipamorelin, tesamorelin, and CJC-1295, are studied for the natural decline in growth hormone that starts in your thirties, and interest in them tends to rise right alongside the GLP-1 conversation about lean mass.
Here's the pricing reality before anyone goes looking. These carry some of the widest per-mg spreads we track. Ipamorelin runs from $2.50 to over $22 a milligram across the vendors we index. Tesamorelin runs from about $4 to nearly $32. When a spread is that wide, brand loyalty is expensive, and the per-mg calculator stops being optional.
What the research actually says
Honestly, thin. The human evidence that any of these preserves muscle during GLP-1 weight loss is limited to small studies and animal work. A recent aging review noted that one CJC-1295 trial program was discontinued and that much of the combination data comes from rodents. These are research compounds, and that's how the evidence reads right now.
The levers with the strongest support are the unglamorous ones the study itself points back to, resistance movement and enough protein to support the muscle you're already using. Not exciting. Just what holds up.
Reply if there's a compound you want us to price-check next week.
Price snapshot: ipamorelin vs. tesamorelin
Both act on the growth hormone axis and both come up constantly in the lean-mass conversation, though they were studied for different things. Ipamorelin is a growth hormone secretagogue. Tesamorelin has actual human trial history behind it for reducing visceral fat.
| Per-mg range | Vendors indexed | |
|---|---|---|
| Ipamorelin | $2.50–$22.59/mg | 32 |
| Tesamorelin | $4.14–$31.80/mg | 30 |
Both drop in per-mg cost at larger vial sizes and climb at the smallest ones, which is normal across the market, not specific to these two. See all current prices
Reader discounts
A few standing codes active this week, all from vendors B-rated or better in our database:
Ascension Peptides (code PPL) is 50% off, the biggest standing discount in our database.
Double R Labs and Soma Chems are both 15% off with code PPL.
Alpha Peptides is 10% off every order, also with code PPL.
Certified-PEP is 30% off with code Certified30.
These are permanent reader codes, not flash sales. PPL earns a commission if you use the affiliate links above, at no cost to you.
The growth hormone peptides discussed here are research compounds, and GLP-1 medications are prescription drugs. Neither is an over-the-counter supplement, and nothing here is medical advice. Prices are current as of the morning this issue went out and can change.