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Blog posts about products, research, and the limits of the evidence.

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48 posts, with sources

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.

Published

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.

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.

Published

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.

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.

Published

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.

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.

Published

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.

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.

Published

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.

A researcher looks through a microscope in a laboratory.

Published Updated

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.

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

Published Updated

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.

Two researchers read notes together at a laboratory table.

Updated

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.

A scientist looks through a microscope in a laboratory.

Updated

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.

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

Published

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.

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.

Published

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.

A person writes in a notebook beside laboratory glassware.

Published

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.

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

Published

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.

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

Published

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.

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

Updated

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.

Clear measuring tubes and glass cylinders arranged in a laboratory.

Updated

Is creatine a peptide?

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

Sample vials and laboratory notebooks on a workbench.

Updated

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.

A row of clear laboratory tubes in a metal rack.

Updated

Is melatonin a peptide?

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

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

Updated

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.

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.

Updated

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.

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

Updated

Is oxytocin a peptide?

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

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

Updated

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.

Two scientists in white laboratory coats standing beside laboratory equipment.

Updated

Is taurine a peptide?

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

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

Updated

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.

A short ivory bead chain beside a folded sage ribbon.

Updated

What are peptides?

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

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

Updated

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.

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

Updated

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.

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