evidence first. every claim carries a source — every recommendation links out no store here · not medical advice · research + education only
inside your peptides.
the insider desk — peptide intelligence

Know what's in the vial
before you believe the label.

The research peptide market runs on claims. We run on documents — trial data, certificates of analysis, FDA import records, payment-network rules. We cover the science, the supply chain, and the business underneath it, and we cite everything.

sources cited no store · we link out updated august 2026
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Peptide fundamentals.

The core knowledge every reader needs before spending a dollar — written to be read once and actually retained.

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latest from the desk

Recent reporting.

Where US Peptide Vendors Actually Get Their Powder

Nearly every vial on the US market starts as bulk API from a small set of overseas synthesizers. FDA's Import Alert 66-80 now detains GLP-1 shipments by default — unless the maker is one of 19 green-listed firms worldwide. Here is how to check a supplier yourself.

The Politics of Peptides in 2026: FDA, Compounding, and the GLP-1 Turf War

Shortage rules built the compounded GLP-1 market and shortage rules are unwinding it. Where telehealth, 503A pharmacies, and research-use vendors actually stand right now.

GLP-1s and Muscle: How Much Lean Mass You Actually Lose

Roughly a quarter to a third of the weight lost on GLP-1 agonists can be lean mass. The trial data, the resistance-training counterweight, and the protein math.

"Tested" Is Not One Thing: Sterility, Endotoxin, and What Certificates Actually Cover

USP <71> sterility, USP <85> endotoxin, and PCR microbial screens are three different tests. Most vendors run one of them at most — and the word "tested" hides the difference.

BPC-157: The Evidence, Graded Honestly

The most-searched healing peptide on the market rests almost entirely on animal data. What the studies show, what they don't, and why WADA bans it anyway.

the sourcing desk

When you're ready to buy.

We don't sell anything. When coverage points somewhere, it points to vendors whose paperwork we can actually verify — and the criteria are public.

disclosure: coverage on this site may earn referral fees from vendors we link to, including the next lab. rankings and grades follow the published criteria in our editorial policy — never referral terms.

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Every compound we cover — what it is, what the evidence grade looks like, and where the research stands.

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what this site is

An evidence desk, not a storefront.

Inside Your Peptides is an independent editorial site covering the research peptide market. We grade compounds by the quality of their published evidence, audit vendors by the quality documents they publish, and report on the infrastructure the market runs on — synthesis and import, payment processing, FDA policy, and lab testing. We sell nothing. When we recommend a source, we link out and disclose the relationship. Every article carries its references.