List of Peptides and What They Do

Every peptide the Bureau covers, grouped by what it is used for, with an honest evidence column next to each one. That last column is the point of this page. Most peptide lists tell you what a compound is claimed to do and stop there, which makes a compound with two phase 3 trials look identical to one with a single mouse study.

Read the evidence column before the description column. The gap between the top and bottom of these tables is enormous, and it is the single most useful thing to understand about this category.

How to Read the Evidence Column

• Approved means a regulator has reviewed it for a named indication. The strongest tier, and it is small.
• Strong means large randomised human trials with published results.
• Phase 2 or 3 means real human trials that are not finished or not yet approved.
• Limited means some human data, usually small, old or narrow.
• Preclinical, animal only or rodent only means no human efficacy trial exists. This covers a large share of what is sold.

The Full List

Metabolic and weight

Repair, recovery and immune

Skin and hair

Growth hormone and muscle

Brain, mood and sleep

Everything else

What Peptides Do for the Body, in General

A peptide is a short chain of amino acids, shorter than a protein. The body uses them as signalling molecules: insulin is a peptide, so is GLP-1, so is growth hormone releasing hormone. They are messages rather than building blocks.

That is why the therapeutic ones work by telling a system to do something it can already do, rather than by supplying a missing material. Semaglutide does not burn fat; it tells the brain the meal was larger than it was. BPC-157 is not tissue; it is proposed to signal repair. Understanding that distinction disposes of most of the marketing in this category, because a signalling molecule can only amplify a process the body is already capable of.

It also explains why most peptides are injected. The digestive system exists to break peptide chains into amino acids, so swallowing one usually destroys it before it does anything. The exceptions are covered in peptide supplements.

The Honest Summary of This List

Counted by evidence tier rather than by popularity, the picture is lopsided. A handful of compounds have approvals or large trials: the GLP-1 class, tesamorelin, PT-141, thymosin alpha-1 in some countries. A second group has real but limited human data. The largest group by far, including several of the most heavily marketed compounds in the category, has animal data and user reports and nothing else.

None of that makes the untested ones worthless to research. It makes them a different proposition, and anyone choosing between a compound with a 20 percent trial result and one with an interesting mouse study should know which is which before paying for either.

Where to Go From Here

• By goal: weight loss, muscle growth, recovery, longevity.
• Practical: reconstitution, injection technique, storage, and the dosing calculator.
• Buying: the vendor scorecard, cost per mg index, how to read a certificate of analysis.
• Context: legal status, what counts as a peptide, cycle lengths.

Frequently Asked Questions

What do peptides do for the body?

Peptides are short chains of amino acids that the body uses as signalling molecules rather than as building blocks. Insulin, GLP-1 and growth hormone releasing hormone are all peptides. Therapeutic peptides work by telling a system to do something it is already capable of: semaglutide does not burn fat, it signals that a meal was larger than it was. That is also why most are injected, since digestion breaks peptide chains into amino acids before they can act.

What is the full list of peptides and what they do?

The tables on this page group every compound the Bureau covers into six categories: metabolic and weight, repair and recovery, skin and hair, growth hormone and muscle, brain and mood, and everything else. Each row gives the common alternative names, a one-line description of the proposed action, and an evidence rating. The evidence column is the important one, because it separates compounds with large randomised trials from those resting on animal studies.

Which peptides actually have strong evidence?

A small group. The GLP-1 class has the strongest data for weight: semaglutide, tirzepatide and retatrutide, with mean reductions of 14.9, 20.9 and 24.2 percent in their respective trials. Tesamorelin is approved for HIV lipodystrophy and has the best data among the growth hormone compounds. PT-141 has an approved formulation for hypoactive sexual desire disorder. Most of the rest of the category has animal data and user reports rather than human efficacy trials.

Which peptides have no human evidence?

More than most lists admit. BPC-157 and TB-500, the two most discussed repair peptides, have no completed human trial. Dihexa has none. MOTS-c has rodent data and human observational correlation but no randomised trials of administering it. 5-Amino-1MQ is rodent only. AOD-9604 did have a human obesity trial and did not separate from placebo on body weight. None of that makes them uninteresting, but it is a different category from an approved drug.

Are peptides the same as proteins?

They are the same kind of molecule at different lengths. Both are chains of amino acids; peptides are the shorter chains, proteins the longer folded ones, with the dividing line drawn by convention rather than by anything physical. The practical difference is that short peptides can act as precise signals at low doses, which is what makes them useful as drugs.

How are peptides usually taken?

Almost all are injected subcutaneously, because the digestive system breaks peptide chains down before they reach circulation. The exceptions are compounds formulated with an absorption enhancer, such as oral semaglutide, compounds whose target is the gut lining itself, and hydrolysed collagen, which works as substrate rather than as a signal. Nasal sprays are used for some smaller peptides such as selank and semax.