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Editorial publication

The Peptide Field

The Peptide Field explains peptide research with links to original studies and official records. The site editor checks claims, source limits, and corrections. That editorial check does not include independent medical review.

Meet Dana Whitcomb, our editorial voice

What you can check

Each post links claims to sources and states where the evidence stops. Cited researchers wrote the source studies. Their names do not imply that they wrote, reviewed, or endorsed this site.

No physician or pharmacist is presented as an independent medical reviewer. Read the review policy or report a correction.

Blog posts from The Peptide Field

Dates show recorded publication or content updates. Original publication dates are not known for every post.

A researcher looks through a microscope in a laboratory.
A researcher uses a microscope in this stock photograph. It does not show a GIP sample or a study result.

GIP: what gastric inhibitory peptide does in the body

Learn what GIP (gastric inhibitory peptide) is, why it has two names, how it helps release insulin after meals, and how tirzepatide differs from it.

Published

A researcher looks through a microscope in a laboratory.
A researcher uses a microscope in this stock photograph. It does not show an Argireline sample or a study result.

Argireline: what wrinkle studies show

Learn what Argireline is, what small wrinkle trials measured, and why a laboratory skin-penetration result cannot predict every serum's effects.

Published

A researcher looks through a microscope in a laboratory.
A researcher uses a microscope in this stock photograph. It does not show a Matrixyl sample or a study result.

Matrixyl peptides: names, wrinkle studies and limits

Compare Matrixyl, Matrixyl 3000 and synthe'6 ingredients. See what two human wrinkle studies found and check whether a cream claim matches them.

Published

A researcher looks through a microscope in a laboratory.
A researcher uses a microscope in this stock photograph. It does not show an antimicrobial peptide sample or a study result.

Antimicrobial peptides: what they do and what studies show

What are antimicrobial peptides? Learn about human defensins, LL-37 and sweat peptides, and how to read laboratory findings without assuming treatment benefits.

Published

A researcher looks through a microscope in a laboratory.
A researcher uses a microscope in this stock photograph. It does not show IGF-1 LR3 or a study result.

IGF-1 LR3: structure and research limits

What is IGF-1 LR3? Compare its structure with natural IGF-1 and see what original cell and animal studies can establish.

Published

A scientist in a white coat handling laboratory glassware beside a chalkboard.
Stock photo of a laboratory scene. It does not show tesofensine, a tested sample, or a study result.

Is tesofensine a peptide?

Is tesofensine a peptide? Check its recorded structure, learn what reuptake inhibitor means, and separate a substance identifier from drug approval.

Published

A scientist in a white coat handling laboratory glassware beside a chalkboard.
Stock photo of a laboratory scene. It does not show peptide production, a tested sample, or a study result.

How are peptides made? Cells and laboratory methods

How are peptides made? Compare cell assembly, chemical synthesis and recombinant production. Learn why a method name cannot prove product quality.

Published

A researcher looks through a microscope in a laboratory.

Cell penetrating peptides: what cell entry proves

Cell penetrating peptide tests can show attachment, trapped cargo, or delivery into cell fluid. Learn what each result proves and where the evidence stops.

Published Updated

A scientist in a white coat works at a laptop in a laboratory.

Is glucagon a peptide?

Yes. Glucagon is a peptide hormone that helps raise blood sugar. Learn its normal role and how it differs from proglucagon and GLP-1.

Published Updated

Two researchers read notes together at a laboratory table.

Is somatostatin a peptide?

Yes. Human somatostatin has 14- and 28-amino-acid peptide forms. Compare both with their 116-unit precursor and with octreotide.

Updated

A scientist looks through a microscope in a laboratory.

Is ghrelin a peptide?

Yes. Human ghrelin has 28- and 27-unit peptide forms. See how its 117-unit precursor and a fatty-acid change affect the names in source records.

Updated

A scientist holds a pipette over a tube in a laboratory.

Is calcitonin a peptide?

Yes. Human calcitonin is a 32-unit peptide hormone. Learn why its precursor has 141 units and how calcitonin differs from procalcitonin and CGRP.

Published

A gloved hand holds a pipette beside test tubes and laboratory glassware.
A gloved hand uses a pipette near test tubes. This stock photo does not show vasopressin, a tested sample, or a study result.

Is vasopressin a peptide?

Yes. Human vasopressin is a nine-unit peptide hormone. See why its precursor has 164 units and how vasopressin differs from copeptin and oxytocin.

Published

A person writes in a notebook beside laboratory glassware.

Is insulin a peptide?

Yes. Human insulin is a peptide hormone also described as a small protein. See how its two chains differ from proinsulin and C-peptide.

Published

A scientist writes on paper beside a microscope and laboratory glassware.

Is GLP-1 a peptide?

Yes, GLP-1 is a peptide hormone. Compare its 30- and 31-unit forms with its precursor, semaglutide, and a nonpeptide receptor agonist.

Published

A person writes in a notebook beside laboratory glassware and a microscope.

Is collagen a peptide?

Collagen is a protein made of peptide-linked chains. Learn how intact collagen, gelatin, and collagen peptides differ, and what each name can tell you.

Published

Conceptual illustration of a brain, a peptide-like ribbon, and a stomach.

How GLP-1 medicines work for weight loss

How does GLP-1 work for weight loss? Learn about appetite, food intake, stomach emptying, and the limits of human studies.

Published Updated

A scientist in a white coat handling laboratory glassware beside a chalkboard.

Is carnosine a peptide?

Is carnosine a peptide? Learn how its two amino-acid units determine its chemical class and what that class cannot show.

Updated

Clear measuring tubes and glass cylinders arranged in a laboratory.

Is creatine a peptide?

Is creatine a peptide? Learn why creatine is an amino-acid derivative rather than an amino-acid chain.

Updated

Sample vials and laboratory notebooks on a workbench.

Is glutathione a peptide?

Is glutathione a peptide? Learn why glutathione is a tripeptide, how its unusual bond works, and what chemical class cannot tell you.

Updated

A row of clear laboratory tubes in a metal rack.

Is melatonin a peptide?

Is melatonin a peptide? Learn why melatonin is an indoleamine rather than an amino-acid chain.

Updated

An amber cluster and an ivory bead chain on separate platforms.

Is MK-677 a peptide?

Is MK-677 a peptide? Learn why ibutamoren is a nonpeptide, what its receptor studies show, and where FDA status and safety evidence stop.

Updated

A dinucleotide-like form and a short amino-acid-like chain on separate platforms.
Conceptual illustration generated with AI. It does not show an exact molecule, product, or study result.

Is NAD a peptide?

Is NAD a peptide? Learn why NAD is a dinucleotide coenzyme and how NAD+, NADH, NMN, and NR differ from peptides.

Updated

A scientist in a white laboratory coat working beside glass lab equipment.

Is oxytocin a peptide?

Is oxytocin a peptide? Learn why oxytocin is a cyclic nine-amino-acid peptide and what that class cannot show.

Updated

A woman wearing yellow safety glasses beside a microscope and laboratory glassware.

Is SLU-PP-332 a peptide?

Is SLU-PP-332 a peptide? Learn what its chemical structure shows and why a catalog label cannot establish chemical class.

Updated

Two scientists in white laboratory coats standing beside laboratory equipment.

Is taurine a peptide?

Is taurine a peptide? Learn why taurine is an amino sulfonic acid rather than an amino-acid chain.

Updated

Loose capsules, fish-oil softgels and white tablets scattered on white marble beside two foil blister packs of pills

Oral peptides: do peptide pills work?

Most oral peptides break down when swallowed. See which FDA-approved peptide pills are built to work, what their studies measured, and how to check a peptide pill claim.

Updated

A short ivory bead chain beside a folded sage ribbon.

What are peptides?

What peptides are, what they may do, safety limits, uses, and product details.

Updated

An ivory bead chain and a copper ring sculpture on separate platforms.

Peptides and steroids: what is different, what is not

A plain-language comparison of peptides and steroids. It covers chemistry, how they send signals, approved medicines, product quality, safety evidence, and the 2026 World Anti-Doping Agency list.

Updated

A product carton with a thick dossier and a pharmacy bottle with an individual record.

Compounded drugs are not FDA-approved products.

Compounded drugs are not FDA-approved and are not reviewed for safety, effectiveness, or quality before marketing. Learn what approval covers, what compounding is for, and how to check a product.

Updated