GLP-1 dosage and evidence
Written by Aaron CuhaReviewed Sep 2026
The short answer
The natural gut hormone behind the whole GLP-1 drug family. You make it after you eat, and it raises insulin and cuts appetite.
Evidence grade for GLP-1: Limited. The rule: people have taken it in a published study, but fewer than 100 of them. The sum on this page: 2 completed trials, 8 people given it. A grade counts how much has been done to people, not whether it works.
- People given it
- 8
- Human studies
- 2
- Found nothing
- 0
Dose
No human dose established
Amounts that were given in studies sit in Human evidence on this page. None of them is a personal dose.
2 completed trials, 8 people given it
1 effects reported, 1 wanted, by people using it, not a trial
Goal pages: Fat loss and metabolism, Gut health
In plain English
In plain English, from Aaron
This is how I would explain it to a friend. The evidence, with the numbers, is further down the page.
GLP-1 is a hormone your gut makes after you eat. It tells your body to release insulin, calms hunger and slows your stomach. Your blood destroys it in about two minutes. Ozempic and Wegovy are a rebuilt version that lasts a week. This page is about the natural hormone, which is not sold as a medicine.
What people take it for
- People do not take natural GLP-1. They take the drugs built from it.
- Those drugs are used for weight loss and type 2 diabetes.
What studies in people showed
The natural hormone has only been tested in small groups. In people with obesity, shots before meals for five days cut food at each meal by about 15 percent. They lost 0.55 kg. A slower stomach is the likely reason. In 8 people with type 2 diabetes after major surgery, a drip brought blood sugar back to normal in about two and a half hours. On a dummy drip it did not. Nobody's blood sugar dropped too low. These tests lasted hours to days. The natural hormone breaks down too fast to be a treatment.
What people report
Reports, not study results
The good
- In the studies on this page, it cut how much people ate and brought blood sugar down, without dropping it too low.
The bad
- We have not collected user reports on this one, because natural GLP-1 is not sold.
Where these come from: The good line is from the two human studies on this page. There are no user reports, because the natural hormone is not sold.
My bottom line
Learn this hormone and the GLP-1 drugs stop being magic. The nausea and the slow stomach are the hormone doing its job. You cannot buy it, and you do not need to.
An opinion, not a finding. I am a coach, not a doctor.
What it has been measured to do
Measured in people
Goals GLP-1 has been tested for in people, biggest studies first. We count only what the studies on this page say, so the real numbers may be higher.
- Blood sugar and insulin8 people · 1 study
- Feeling less hungryno headcount stated · 1 study
- Losing weightno headcount stated · 1 study
- Gut and digestionno headcount stated · 1 study
32 of the 36 indexed goals have no study of any kind behind GLP-1
No study in people, animals or cells on this page reports a result for these. That does not prove GLP-1 does nothing for them. It does mean anything you have heard about GLP-1 and one of these did not come from a study cited here.
Show full evidence
What is GLP-1?
The natural gut hormone behind the whole GLP-1 drug family. You make it after you eat, and it raises insulin and cuts appetite.
First, what confuses people. This page is about the hormone your own gut makes, not about Ozempic. The legal status below says not approved because nobody sells natural GLP-1 as a medicine. Nobody can: your blood destroys it in about two minutes. Ozempic and Wegovy are semaglutide. That is a rebuilt version that lasts a week, and it is approved. Same switch, different molecule.
Your gut releases GLP-1 after meals. It raises insulin, turns down glucagon, slows how fast food leaves your stomach and cuts appetite. That two-minute life is the whole reason the drug family exists. Every approved GLP-1 medicine is a way to keep this signal on longer than the body allows. In 8 people with type 2 diabetes after major surgery, a drip of natural GLP-1 brought blood sugar back to normal within about two and a half hours. In people with obesity, shots before meals for five days cut food at each meal by about 15% and took off 0.55 kg. Knowing the hormone helps you understand what the drugs do, and why they do what the hormone does, including the nausea and the slow stomach.
How does GLP-1 work?
It switches on GLP-1 receptors. That releases insulin when blood sugar is high, turns down glucagon, slows how fast food leaves your stomach and cuts how much you eat.
The evidence, in charts
Fig. 1a · how many people
8people, across 1 study in people cited here
| Study | People | Share |
|---|---|---|
| Critical Care Medicine 2004 | 8 | 100% |
The whole total is one study of 8. Counts are the number of people each study on this page says it signed up. That includes studies that only watched people and gave nobody the compound. 1 more study in people gives no headcount and is not counted here. Studies still signing people up are left out, and only studies cited on this page are counted.
Fig. 1b · evidence mix
2 of 5 sources here are studies in people. The rest are not.
- Study in people · done in people240%
- Review of studies · sums up other studies360%
Counted from the list of sources on this page. It counts only what we cite, so there may be more studies out there. A review counts once, however many studies it sums up.
Fig. 2 · evidence over time
The studies cover 4 different years, 2004 to 2023, counted from the list of sources on this page.
Fig. 3 · legal status at a glance
US
Not approved
UK
Not approved
AU
Not approved
CA
Not approved
Not approved in any of the four countries shown. This is what the law says, not a verdict on the science. See Legal status below for the full text and any notes.
Fig. 4 · how much does what
Nobody has tested different amounts in people
This chart would show how the effect changes as the amount goes up. For this compound, nobody has measured that in people. So we leave it empty. We will not borrow an animal chart and pretend it works the same in people.
Fig. 5 · what the molecule is
- Kind of compound
- Peptide
- Molecule weight
- 3,297.7 Da
- Half-life
- About 2 minutesUltra-short, minutes
- Chain length
- None on file
No amino acid sequence is on file for GLP-1, so none is drawn rather than guessed from a name.
The studies we cite
- Study in people2004Intravenous glucagon-like peptide 1 normalizes blood glucose after major surgery in patients with type 2 diabetes
The natural hormone brought blood sugar back to normal after major surgery. Eight people with type 2 diabetes were treated twice, once with a GLP-1 drip and once with a dummy. On the hormone, blood sugar reached the normal fasting range within about two and a half hours. On the dummy it did not. Insulin rose, glucagon fell, and nobody's blood sugar dropped too low. Eight people is about as small as a trial gets, and this was hours in a hospital, not a treatment.
Randomized crossover in eight patients with type 2 diabetes after major surgery. An eight-hour infusion of native GLP-1 brought plasma glucose into the normoglycemic fasting range within 150 minutes while placebo did not, raising insulin and C-peptide and suppressing glucagon, with no hypoglycemic events.
- Study in people2004Prandial subcutaneous injections of glucagon-like peptide-1 cause weight loss in obese human subjects
The hormone your own gut makes does what the drugs built from it do, only briefly. Adults with obesity injected native GLP-1 before meals for five days, and also spent a period on a dummy, with nobody knowing which. Food eaten at each meal fell by about 15 percent and they lost 0.55 kg. Food leaving the stomach more slowly is the likely reason. Five days is a short test and half a kilo is small. The natural hormone breaks down far too fast to be a treatment.
Randomized double-blind placebo-controlled crossover in healthy obese subjects with a mean BMI of 39. Five days of native GLP-1 given before meals cut mean food intake per meal 15% and produced 0.55 kg of weight loss, with slowed gastric emptying as the probable mechanism. The native hormone does what its analogues do, just far more briefly.
- Review of studies2007The physiology of glucagon-like peptide 1
Holst's major review of GLP-1. It covers how it is released and broken down, and how it raises insulin, lowers glucagon, slows the stomach and cuts appetite.
Holst's definitive review of GLP-1 secretion, degradation and incretin, glucagon-suppressing, gastric and appetite actions.
- Review of studies2019Glucagon-like peptide 1 (GLP-1)
A broad review of GLP-1 and the drugs built on it, in metabolic disease and brain disease.
Comprehensive review of GLP-1 biology and pharmacology across metabolic and neurodegenerative disease.
- Review of studies2023The expanding incretin universe: from basic biology to clinical translation
A review of how GIP and GLP-1 boost insulin and control glucagon, and how that science became the drugs in this family.
Reviews how GIP and GLP-1 potentiate insulin and regulate glucagon, and how that biology translated into incretin-based drugs.
Where to buy GLP-1
47 sellers list GLP-1 in our latest read. They are ranked by trust score, then by archive rating, then by certificate tier, then by the lowest price per milligram. Archive evidence is counted before source-backed. Each path is out of 4, and the two are not added. A higher price does not raise the score. The letter is the certificate chip. 0 of them have a published certificate that names GLP-1.
Some seller links may pay this site when you buy through them. A payment never changes a seller's tier or rank, and no seller has a say in any page.
| Seller | Trust score | Vial sizes | From, per mg | Certificate for GLP-1 | Seller link |
|---|---|---|---|---|---|
| Alpha Peptides | 80 StrongSource-backed 4 of 4. Archive evidence 2 of 4.A | 5 mg, 10 mg | $6.50 | None found for GLP-1 | View |
| Secra Labs | 80 StrongSource-backed 4 of 4. Archive evidence 2 of 4.A | 10 mg | $7.50 | None found for GLP-1 | View |
| BioGenix Peptides | 75 StrongSource-backed 4 of 4. Archive evidence 2 of 4.A | 10 mg, 20 mg | $5.75 | None found for GLP-1 | View |
| Xeno Peptides | 73 StrongSource-backed 4 of 4. Archive evidence 2 of 4.A | 20 mg | $3.00 | None found for GLP-1 | View |
| Area 15 Labs | 73 StrongSource-backed 4 of 4. Archive evidence 2 of 4.A | 10 mg, 30 mg | $3.33 | None found for GLP-1 | View |
| Restore Peptides | 73 StrongSource-backed 4 of 4. Archive evidence 2 of 4.A | 3 mg | $16.7 | None found for GLP-1 | View |
| Peak Lab Peptides | 73 StrongSource-backed 3 of 4. Archive evidence 2 of 4.A | 5 mg, 10 mg, 15 mg, 20 mg, 30 mg, 40 mg, 50 mg, 60 mg | $2.96 | None found for GLP-1 | View |
| Elite Research Lab | 73 StrongSource-backed 3 of 4. Archive evidence 2 of 4.A | 10 mg, 15 mg, 20 mg | $3.00 | None found for GLP-1 | View |
| MedVinci Research | 73 StrongSource-backed 3 of 4. Archive evidence 2 of 4.A | 15 mg | $4.00 | None found for GLP-1 | View |
| Accelerate Labs | 72 StrongSource-backed 4 of 4. Archive evidence 2 of 4.A | 5 mg, 10 mg | $9.00 | None found for GLP-1 | View |
| Simons RX | 70 StrongSource-backed 4 of 4. Archive evidence 2 of 4.A | 5 mg, 10 mg, 20 mg | $11.3 | None found for GLP-1 | View |
| Lifestyle Peptides | 70 StrongSource-backed 3 of 4. Archive evidence 2 of 4.A | 5 mg | $28.0 | None found for GLP-1 | View |
| Rejuven8 Peptides | 63 FairSource-backed 4 of 4. Archive evidence 2 of 4.A | 10 mg, 20 mg, 30 mg | $3.83 | None found for GLP-1 | View |
| Kalyx Labs | 62 FairSource-backed 3 of 4. Archive evidence 2 of 4.A | 10 mg, 20 mg | $4.50 | None found for GLP-1 | View |
| Revitalized Research | 62 FairSource-backed 3 of 4. Archive evidence 2 of 4.A | 5 mg, 10 mg | $6.00 | None found for GLP-1 | View |
| Tex Peptides | 58 FairSource-backed 4 of 4. Archive evidence 1 of 4.B | 10 mg, 20 mg | $7.50 | None found for GLP-1 | View |
| House of Compounds | 54 FairSource-backed 2 of 4. Archive evidence 2 of 4.B | 10 mg, 20 mg, 30 mg | $4.00 | None found for GLP-1 | View |
| Honest Peptide | 49 WeakSource-backed 3 of 4. Archive evidence 2 of 4.A | 5 mg, 10 mg | $9.00 | None found for GLP-1 | View |
| Liberty Peptides | 49 WeakSource-backed 3 of 4. Archive evidence 2 of 4.A | 6 mg, 10 mg | $10.8 | None found for GLP-1 | View |
| 6 Labz | 49 WeakSource-backed 3 of 4. Archive evidence 2 of 4.A | 5 mg, 10 mg | $11.6 | None found for GLP-1 | View |
| Research Purpose Labs | 49 WeakSource-backed 3 of 4. Archive evidence 2 of 4.A | 5 mg, 10 mg, 15 mg | $16.7 | None found for GLP-1 | View |
| BioFusion Aminos | 49 WeakSource-backed 2 of 4. Archive evidence 2 of 4.B | 5 mg, 20 mg | $12.5 | None found for GLP-1 | View |
| Pepvida Labs | 49 WeakSource-backed 3 of 4. Archive evidence 1 of 4.A | 5 mg | $11.8 | None found for GLP-1 | View |
| Peplogix | 49 WeakSource-backed 3 of 4. Archive evidence 1 of 4.B | 5 mg, 10 mg, 30 mg | $10.8 | None found for GLP-1 | View |
| Value Research Labs | 43 WeakSource-backed 3 of 4. Archive evidence 2 of 4.A | 10 mg, 20 mg, 30 mg | $2.67 | None found for GLP-1 | View |
| Alpha Pro Peptides | 43 WeakSource-backed 1 of 4. Archive evidence 1 of 4.C | 5 mg | $7.00 | None found for GLP-1 | View |
| Pryma Lab | 43 WeakSource-backed 1 of 4. Archive evidence 0 of 4.C | 5 mg | $12.0 | None found for GLP-1 | View |
| Peptides.com | 42 WeakSource-backed 2 of 4. Archive evidence 2 of 4.B | 5 mg, 10 mg, 20 mg | $6.50 | None found for GLP-1 | View |
| Innovative Peptides | 40 WeakSource-backed 3 of 4. Archive evidence 1 of 4.B | 5 mg, 10 mg, 15 mg | $5.33 | None found for GLP-1 | View |
| APR Health Solutions | 40 WeakSource-backed 1 of 4. Archive evidence 1 of 4.C | 10 mg | $7.00 | None found for GLP-1 | View |
| Swift Peptides | 40 WeakSource-backed 1 of 4. Archive evidence 1 of 4.C | 5 mg, 10 mg | $8.70 | None found for GLP-1 | View |
| Peptides Lab UAE | 40 WeakSource-backed 1 of 4. Archive evidence 1 of 4.C | 5 mg | $15.8 | None found for GLP-1 | View |
| Better Nak'd Aminos | 38 WeakSource-backed 2 of 4. Archive evidence 1 of 4.B | 10 mg, 20 mg, 30 mg | $9.60 | None found for GLP-1 | View |
| Peptides For Less | 36 WeakSource-backed 1 of 4. Archive evidence 1 of 4.C | 20 mg, 50 mg | $2.80 | None found for GLP-1 | View |
| Republic Peptide | 33 WeakSource-backed 1 of 4. Archive evidence 1 of 4.C | 15 mg | $2.93 | None found for GLP-1 | View |
| VM Peptides | 33 WeakSource-backed 1 of 4. Archive evidence 1 of 4.C | 20 mg | $5.00 | None found for GLP-1 | View |
| BioStrata Research | 30 WeakSource-backed 2 of 4. Archive evidence 1 of 4.C | 10 mg, 30 mg | $3.97 | None found for GLP-1 | View |
| Vertex Labs | 30 WeakSource-backed 1 of 4. Archive evidence 1 of 4.C | 10 mg, 20 mg, 30 mg | $3.95 | None found for GLP-1 | View |
| Soma Peptides | 29 InsufficientSource-backed 4 of 4. Archive evidence 1 of 4.Letter withheld | 5 mg, 10 mg, 30 mg | $12.3 | None found for GLP-1 | View |
| Boston Molecules | 28 InsufficientSource-backed 1 of 4. Archive evidence 1 of 4.C | 10 mg | $81.0 | None found for GLP-1 | View |
| Northline Labs | 26 InsufficientSource-backed 1 of 4. Archive evidence 1 of 4.C | 10 mg, 15 mg, 20 mg, 30 mg, 50 mg | $2.38 | None found for GLP-1 | View |
| True Research Labs | 25 InsufficientSource-backed 1 of 4. Archive evidence 1 of 4.C | 10 mg, 20 mg, 30 mg | $2.80 | None found for GLP-1 | View |
| ThreeSide Peptides | 25 InsufficientSource-backed 1 of 4. Archive evidence 1 of 4.C | 5 mg, 10 mg, 20 mg, 30 mg | $4.67 | None found for GLP-1 | View |
| Pure Health Peptides | 25 InsufficientSource-backed 1 of 4. Archive evidence 0 of 4.C | 5 mg, 10 mg, 15 mg, 20 mg, 30 mg | $3.63 | None found for GLP-1 | View |
| Wellness Peptides | 10 InsufficientSource-backed 3 of 4. Archive evidence 0 of 4.Letter withheld | 5 mg, 10 mg | $9.00 | None found for GLP-1 | View |
| Platinum Lion Peptides | 0 InsufficientSource-backed 3 of 4. Archive evidence 1 of 4.Letter withheld | 10 mg, 20 mg | $5.00 | None found for GLP-1 | View |
| Apex Peptides | 0 InsufficientSource-backed 1 of 4. Archive evidence 0 of 4.Letter withheld | 5 mg, 10 mg, 12 mg | $29.2 | None found for GLP-1 | View |
- LC Lab-confirmed: the issuing laboratory echoed this certificate back
- A Current certificate, independent laboratory named, laboratory not yet checked
- B Certificate published, but no laboratory link, older than a year, or the laboratory did not recognise the published lookup
- C No certificate could be read
Every listing and vial size for GLP-1 · How the trust score is counted
Sellers named on the price pages are ranked by certificate tier, then price, and any affiliate income is disclosed there. Naming a seller is not a recommendation to buy or use anything.
Common questions
Has GLP-1 been tested in people?
Yes. 8 people given it across 2 completed trials cited here, 0 of which found nothing. The natural gut hormone behind the whole GLP-1 drug family. You make it after you eat, and it raises insulin and cuts appetite.
What is the GLP-1 dosage?
No human dose established. Amounts that were given in studies sit in Human evidence on this page. None of them is a personal dose. 2 completed trials, 8 people given it
Is GLP-1 FDA-approved?
The hormone itself is not a medicine and is not sold as one. The drugs built from it are approved: semaglutide (Ozempic, Wegovy, Rybelsus), liraglutide, dulaglutide, exenatide and tirzepatide all act at this receptor and are FDA-approved prescription medicines.
Why not just use native GLP-1?
Your body breaks down natural GLP-1 within a couple of minutes. Drugs like semaglutide are rebuilt versions that resist breakdown, so the effect lasts for days.