Peptides 101: A Plain-Language Guide
What peptides are, how approved medicines differ from experimental compounds, and how to judge the health claims you see online.
Peptides are short chains of amino acids, the same building blocks that make up proteins. Your body makes thousands of them. Some act as hormones, some help fight infection, and some help control blood sugar or appetite.
Peptides you already know
- Insulin has been used to treat diabetes since the 1920s.
- Oxytocin is given in hospitals during childbirth.
- GLP-1 medicines are prescribed for type 2 diabetes and weight management.
- Collagen peptides are sold as foods and supplements and are regulated as food rather than drugs.
Approved versus experimental
Before a medicine is approved, it goes through large human trials, and a regulator such as the FDA reviews its safety, how well it works and how it is made. Many peptides discussed online have not been through that process. Some have only been tested on cells in a dish or in animals, and results in animals often don’t carry over to people.
How to judge a health claim
- Was the evidence gathered in people, in animals or in a lab dish?
- Was there a randomized trial with a placebo group?
- Has a regulator approved the product for the use being claimed?
- Does one product supposedly fix many unrelated problems?
- Does the source also sell the product it is describing?
How we cover peptides
Every article on this site lists its sources, explains what kind of evidence exists and states the compound’s regulatory status. We don’t sell anything, link to sellers or give dosing advice. You can read more in our editorial policy.
This guide is for general information and is not medical advice. Talk to a licensed healthcare provider about any treatment.