About

What this is

Learning Health is a reading room for peptide science. One report per compound, built the same way each time, written so that someone without a pharmacology background can see what is actually known — and, more often, what is not.

It exists because the information available on these compounds is split between two unhelpful extremes. On one side, the primary literature: accurate, paywalled, and written for specialists. On the other, forums and sellers: readable, confident, and frequently wrong in the same predictable ways — a rat study described as proof, a mechanism described as an outcome, a regulator’s inaction described as approval.

The gap between those two is where most people actually make decisions. This site is an attempt to fill it without taking a position on what anyone should do.

Who it is for

Someone who has heard a peptide mentioned and wants to know whether there is anything behind it. Someone who has been handed a claim and wants to check it. Someone trying to understand why a compound can be simultaneously legal, unapproved, banned in sport and backed by almost no human data — which describes several entries in this atlas.

It is not written for clinicians, though the references are there if you want them. It is not written for people looking for instructions, and it does not contain any.

What it refuses to be

A shop. Nothing is for sale here and nothing is advertised. Compound names in the reports link to a partner store — the site’s only commercial link — and no report is sponsored.

A protocol library. No dosing guidance, no cycles, no stacking, no instructions of any kind. Reports say what a study administered, because that is part of the evidence; they never say what you should do.

An advocate. We are not for or against peptides. Of the seventeen compounds here, one is an approved drug, three are ordinary cosmetic or food ingredients, and the rest range from genuinely promising to barely characterised. Treating that spread as one topic with one answer is the mistake this site is built to avoid.

A substitute for a clinician. Read the medical disclaimer. It is short and it is meant literally.

How the reports are produced

Each report starts from the primary literature — searches of PubMed for every human study, systematic review and key mechanistic paper on the compound — plus the relevant primary regulatory documents. Numbers are taken from the papers themselves. Study designs are stated, because a result from an uncontrolled series of twelve people and a result from a randomised trial of eleven hundred are not the same kind of thing, and the difference is usually invisible in how they get quoted.

The full method, including the source hierarchy and what gets excluded, is on the editorial standards page. The grading system is explained in how we grade evidence.

What we would like you to take away

If you read nothing else here, four questions will serve you well on any health claim, peptide or otherwise: who was studied — cells, animals or people; was there a control group; who paid; and is the product the same thing that was studied. Those four questions resolve most of what is argued about in this field.

The second takeaway is subtler. An absence of evidence is not evidence of absence — several compounds here may well turn out to work. But it is also not a reason for confidence, and it is the single most common thing to be misrepresented. “Promising” and “proven” are separated by the entire apparatus of clinical research, and most of these compounds have not been through it.

Contact

Corrections are welcome, particularly on regulatory status, which changes faster than anything else on this site. If you can point to a primary source that contradicts something here, that is exactly the message worth sending.