Research Library
Peptide research, regulatory updates, and protocol intelligence.
Grounded in peer-reviewed literature and FDA prescribing data — the same sources that power the PeptidesGPT AI Coach.
Before EASD: How to Read a Confidence Interval (And Why It Matters This Week)
EASD Milan opens this week with ACHIEVE-4 cardiovascular data for Foundayo. Before '16% lower cardiac risk' runs in every headline, here's what the confidence interval actually says — and why it matters.
Are GLP-1 Users Becoming Undernourished? What a 19-Trial Meta-Analysis Found
A systematic review of 19 randomized trials found a significant gap between clinician-reported malnutrition and lab-detected nutritional deficits in GLP-1 users. Here's what the data shows — and what it means for anyone on a GLP-1 protocol.
What Happens When You Stop: The Real Weight Regain Data After GLP-1 Therapy
A new Bayesian analysis of 1,776 adults quantifies weight regain trajectories after stopping semaglutide or tirzepatide. Here's what the data shows — and where the analysis ends and the projection begins.
The Race to Put GLP-1, Amylin, and Obesity Medicine in a Pill: The Full Oral Metabolic Drug Tracker
From oral semaglutide to once-weekly oral peptide GLP-1s to oral amylin agonists — the oral obesity drug pipeline is more advanced than most people realize. Here's the complete tracker as of September 2026.
Oral Amylin and the Next Frontier in Obesity Medicine: What Structure Therapeutics Just Showed
Structure Therapeutics reported the first human data for an oral small-molecule amylin agonist and 72-week results for its oral GLP-1. Here's what the data shows and why oral combination therapy may be where this is heading.
Does Semaglutide Increase Depression Risk? A Korean Study Says Yes — But the Answer Isn't Settled.
A 13-hospital Korean cohort study found semaglutide associated with a 3.42x higher depression hazard. It conflicts with three larger data sources. Here's what each actually shows.
Semaglutide in Children Ages 6–11: The Clinical Breakthrough — and the Questions We Now Have to Answer
Novo Nordisk's STEP Young Phase 3 found that 40.4% of children ages 6-11 with obesity were no longer classified as having obesity at 68 weeks on semaglutide. Here's what the data shows — and what it doesn't.
GLP-1 2.0: Why Weight Loss Is Only the Beginning
GLP-1 1.0 asked: how much weight can you lose? GLP-1 2.0 asks something harder: what health can you gain? Here's why the entire frame of GLP-1 medicine is shifting — and what it means for anyone running a protocol.
GLP-1 Obesity Drug Efficacy Ranked: What 38 Randomized Trials and 25,816 Adults Actually Show
An updated systematic review pooled 38 randomized trials and 25,816 adults without diabetes. Here's the placebo-adjusted weight loss hierarchy for every major GLP-1 drug — and what the numbers actually mean.
Semaglutide Extended Lifespan in Female Mice. Here's What That Does and Doesn't Mean.
A 2026 Nature study found semaglutide started late in life extended lifespan and improved function in female mice. Some benefits exceeded caloric restriction alone. Here's what the evidence actually shows — and what it doesn't.
FDA Says Discard Your Compounded GLP-1 Vial After 28 Days. Here's What That Actually Means.
FDA updated its compounded GLP-1 safety guidance: discard multi-dose vials 28 days after first use, regardless of what the compounder's label says. Here's what changed, why it matters, and what to do.
FDA Warned Five Peptide Sellers the Same Day. 'Research Use Only' Was Not a Shield.
FDA posted five warning letters to peptide sellers on September 1, 2026, all dated August 24 from a July sweep. The RUO disclaimer didn't protect them. Here's what FDA actually looked at.
Retatrutide vs. Tirzepatide and Anhedonia: The Only Real Variable, and the Data Nobody Has Published
GIP is shared between retatrutide and tirzepatide — it cannot explain the difference in anhedonia reports. Glucagon is the only real variable, and its connection to mood may have nothing to do with dopamine.
Tesamorelin Cut Visceral Fat by 27 cm². Every Trial Was in HIV-Associated Lipodystrophy.
A 2026 meta-analysis of five randomized trials found tesamorelin reduced visceral fat by 27.71 cm² and hepatic fat by 4.28% — in adults with HIV-associated lipodystrophy. What that shows, and what it does not.
Lilly Filed 6 Lawsuits Against Retatrutide Sellers. The Real Target Is the Infrastructure.
Eli Lilly filed six federal lawsuits against alleged retatrutide sellers on August 12, 2026. The lawsuits are the visible part. The 200+ referrals and 14,000+ listings are the actual campaign.
Purity, Identity, and Quantity: Three Different Questions Your COA May Not Be Answering
A 99% purity result answers one question. It does not answer whether the compound is correctly identified, or how much is actually in the vial. When researchers tested products from online sellers, the answers diverged badly.
Eloralintide — The Complete Research Guide: What the Phase 2 Data Shows and Why the Amylin Story Changes Everything
Eloralintide (LY3841136) is Eli Lilly's selective amylin receptor agonist. Phase 2 published in The Lancet showed up to 20.1% weight loss at 48 weeks at the highest dose. Here's what the data actually shows.
Retatrutide Just Won Two More Phase 3 Trials. Here's What TRIUMPH-2 and TRIUMPH-3 Actually Show.
Eli Lilly announced positive Phase 3 results from TRIUMPH-2 and TRIUMPH-3 on July 23, 2026. Here's what the data shows — and what it means for the future of obesity and cardiovascular medicine.
GLP-1 Anhedonia — When the Food Noise Goes Quiet and Everything Else Does Too
Some GLP-1 users experience more than appetite suppression — motivation, pleasure, and enjoyment can flatten too. Here's what anhedonia on GLP-1s actually is, why it happens, and how to track it.
The Longevity Dashboard — What to Track, How Often, and Why Most Platforms Miss the Point
Most longevity tracking platforms aggregate data but can't interpret it in context of your protocol. Here's what a real longevity dashboard tracks, how to structure it, and the one layer every platform misses.
BPC-157 and TB-500 After the FDA Panel Vote — What the Research Shows
An FDA advisory panel voted 8-6-1 to recommend BPC-157 and TB-500 for compounding — over the objections of the agency's own scientists. Here is what the vote did and did not do, and what the evidence base actually supports.
PCAC Final Results: 6 of 7 Peptides Recommended for Compounding. Here's the Complete Breakdown.
The FDA's PCAC recommended 6 of 7 peptides — BPC-157, TB-500, KPV, MOTS-c, Semax, Epitalon — for 503A compounding. Full vote tally and what happens next.
The FDA Advisory Committee Just Voted 8-6 to Recommend BPC-157 for Compounding. Here's What It Means.
The FDA's Pharmacy Compounding Advisory Committee voted 8-6-1 to recommend BPC-157 for the 503A Bulks List on July 23, 2026 — overriding FDA staff. Here's what the vote means, what it doesn't mean, and what happens next.
FDA Staff Opposes All 7 Peptides. Here's What That Actually Means — and What Happens Next.
FDA staff briefing documents recommend against adding BPC-157, TB-500, MOTS-c, KPV, Semax, Epitalon, and Emideltide to the 503A Bulks List. Here's what the recommendation means, why FDA reached it, and what actually happens next.
My Bloodwork Was Perfect. I Had a 99% Blockage.
My biomarkers looked optimal. My primary care doctor saw nothing to worry about. Then imaging showed a 99% blockage in my RCA and 80% in my LAD. Here's what bloodwork can't tell you.
Bloomberg Just Put Peptides on the Cover. Here's What It Got Right — And What the Story Missed.
Bloomberg Businessweek's peptide cover story describes a multibillion-dollar gold rush. Here's the context the article didn't have space to explain — and what it means for anyone navigating this space.
Why I Stopped Chasing My Goal Weight — And What I Track Instead
I hit my goal weight of 168 lbs — and my body composition data told a different story: muscle down, body fat up. Here's why I track SMM and body-fat %, not just the scale.
What Lilly's Top Obesity Executive Just Said About the Future of Metabolic Medicine
At the Goldman Sachs 47th Annual Healthcare Conference, Lilly's EVP of Cardiometabolic Health framed GIP, GLP-1, and amylin as the three hormones that belong together. Here's what that signals.
You're on a GLP-1. Here's Why You Need a System Before You Stop
The compounded GLP-1 market closes June 29, 2026. STEP 1 trial data shows ~2/3 of lost weight returns after stopping. Here's how to build a tracking system before access changes.
BPC-157's First Randomized Human Clinical Trial: What NCT07437547 Actually Tells Us
NCT07437547 — BPC-157 for acute hamstring strain: sponsor, phase, enrollment, endpoints and current status, plus what this Phase 2 trial does not test.
The GLP-1 Rebound Problem: What the Clinical Data Actually Shows — and What to Do About It
Two-thirds of weight lost on semaglutide returns within 12 months of stopping. The STEP 1 and SURMOUNT-4 trial data explains why — and what the research says actually helps.
TRIUMPH-1: Why the Most Interesting Number in Retatrutide's Phase 3 Trial Isn't 28%
Eli Lilly's TRIUMPH-1 Phase 3 trial showed 28% weight loss at 12mg retatrutide. But the real story is in the 4mg column — and it changes how most patients should think about this drug.
Women, GLP-1s, and Lean Mass: What the Research Actually Shows About Muscle Preservation During Fat Loss
GLP-1 medications cause both fat and muscle loss in women. Here's what the research says about preserving lean mass during fat loss — and why it matters more than the number on the scale.
How Long Can You Stay On Peptides? Why Mechanism Changes the Question
Cycle length advice usually ignores mechanism. Here is why receptor agonists, signal modulators, and repair compounds raise different duration questions — and where the human evidence runs out.
BPC-157, TB-500, and Epithalon: What's Actually Happening with FDA Reclassification in 2026
BPC-157 and TB-500 left the FDA's Category 2 restricted list on April 23, 2026. The FDA's PCAC meets July 23–24 to formally review 7 peptides for 503A approval. Here's what actually happened.
Forzinity (SS-31) Receives FDA Accelerated Approval — Here's What It Means for the Peptide Field
SS-31 (Forzinity) received FDA accelerated approval in September 2025 for mitochondrial dysfunction — the first peptide of its class to cross from gray market to approved drug.
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