What peptides are
Amino acids are small molecules that can link together in chains. A peptide is a short chain of amino acids joined by chemical bonds known as peptide bonds. The National Human Genome Research Institute describes peptides as typically 2 to 50 amino acids long. Source: NHGRI Genetics Glossary, “Peptide” (external source)
The particular amino acids involved, and the order in which they appear, give each peptide its own identity.
How peptides differ from proteins
The main difference is size. According to NHGRI, a longer chain of 51 or more amino acids is called a polypeptide, and the proteins made inside cells consist of one or more polypeptides. Source: NHGRI (external source)
Regulators may draw the line differently. For example, U.S. federal regulations define a protein as an amino acid polymer with a specific, defined sequence that is greater than 40 amino acids in size. Source: 21 CFR 600.3(h)(6) (external source)
In other words, “peptide” and “protein” describe points along a scale, and the exact boundary depends on who is drawing it and why.
Why “peptide” covers many different substances
Because the word describes a structure rather than a purpose, it applies to an enormous range of molecules. Two peptides can share the label while differing completely in what they do, how they are made, how thoroughly they have been studied and how they are regulated.
Knowing that something is a peptide tells you its general structure. It does not tell you what it does, whether it is approved, or whether it is safe for you.
Approved medicines, supplements and research compounds
Products that involve peptides can fall into very different categories. The examples below use the United States as a reference point; other countries have their own regulators and definitions.
Approved medicines
A drug is approved by the FDA after the agency reviews the manufacturer’s data and determines that the drug’s benefits outweigh its known and potential risks for the intended population. FDA: Development & Approval Process (external source) You can look up approved products in the Drugs@FDA database (external source).
Dietary supplements
The FDA states that it does not have the authority to approve dietary supplements before they are marketed, and that manufacturers and distributors have initial responsibility for their products’ safety. FDA: Questions and Answers on Dietary Supplements (external source)
Research compounds
A substance can be the subject of laboratory, animal or human studies without being approved. FDA approval comes only after evidence has been gathered and reviewed. FDA (external source) Research interest alone does not establish safety or effectiveness.
Why each substance must be considered on its own
Because peptides vary so widely, general statements rarely apply across the board. For any specific substance, three things deserve attention:
- Evidence. What kind of research exists, and how strong is it?
- Regulatory status. Is it approved, and if so, for which use and in which country?
- Safety. What risks are known, and what is still unknown?
The FDA has identified a number of peptide substances nominated for use in drug compounding that may present significant safety risks, citing concerns such as possible immune reactions, impurities and, in several cases, insufficient information to know whether the substance would cause harm. Source: FDA: Bulk Drug Substances That May Present Significant Safety Risks (external source)
Questions to discuss with a qualified healthcare professional
Bringing questions to an appointment can make the conversation more useful. MedlinePlus (external source) offers general guidance on talking with your doctor. You might ask:
- What is this substance, and what is its regulatory status where I live?
- What does the current evidence show, and how strong is it?
- What are the known risks or side effects, and what is not yet known?
- Could it interact with my medicines, supplements or existing health conditions?
- Is it relevant to my situation at all, and are there established alternatives?
- How can I tell whether a product’s source and quality are reliable?
Frequently asked questions
What is a peptide?
A peptide is a short chain of amino acids joined by chemical bonds called peptide bonds. The U.S. National Human Genome Research Institute describes peptides as typically containing 2 to 50 amino acids (NHGRI (external source)).
Are all peptides the same?
No. “Peptide” describes a type of molecular structure, not a single substance. Different peptides have different sequences, roles, regulatory status and safety profiles, so each one has to be considered individually.
Does research mean a product is approved for human use?
No. Being studied is not the same as being approved. In the United States, a drug is approved only after the FDA reviews evidence and determines that its benefits outweigh its known and potential risks for the intended population (FDA (external source)). Other countries have their own regulators and rules.
Where do I find current product availability?
Current availability and pricing are shown only on our separate store, in the Wellness Management collection (opens the Wellness Management collection on the separate King Reta store). This website lists product names, SKUs and laboratory reports for reference, but it does not sell products.
Where are orders and payments handled?
All orders, payments and checkout are handled on the separate King Reta store. This website does not take orders or process payments.