Exosomes are the buzzword of the moment. Growth factors have been around for years. And stem cell conditioned media contains both. No wonder people are confused.
Here's what each one is, how they relate and how to read a label so you know what you're actually buying.
The short version
| Growth factors | Exosomes | Conditioned media | |
|---|---|---|---|
| What it is | Individual signaling proteins | Tiny vesicles cells use to send packages of signals | The whole mix stem cells release as they grow |
| Contains | One or a few proteins | Proteins, lipids and genetic messengers inside a membrane | Growth factors, exosomes, peptides, antioxidants |
| Analogy | A single text message | A sealed envelope with several messages | The whole mailbag |
Growth factors
Growth factors are proteins your cells use to tell each other when to grow and renew. In skincare, they can come from human cells, from the lab or from plants. Some products use one isolated growth factor; others use a natural mix. Read more in our guide to the growth factor serum.
Exosomes
Exosomes are extremely small vesicles, a type of extracellular vesicle, that cells release to carry signals to other cells. Their membrane protects what's inside. In skincare they can come from human stem cells, platelets, plants or even milk, and the source makes a big difference. Read our full guide to exosomes in skincare.
Stem cell conditioned media
When stem cells grow in a lab, they release growth factors, exosomes, peptides and other molecules into the liquid around them. That liquid, purified, is stem cell conditioned media. Rather than isolating one signal, it keeps the natural mix together.
That "whole mailbag" approach is the one Dr. Joy Kong chose for CharaOmni: conditioned media from donated umbilical cord tissue and amniotic membrane, in a cream with hyaluronic acid and natural oils, so the full mix of signals goes on in one daily step.
Growth factors are the messages. Exosomes are the envelopes. Conditioned media is everything the stem cells sent.
Which one works best?
There's no simple winner. A 2025 systematic review analyzed 19 clinical studies on conditioned media and extracellular vesicles (which include exosomes) for skin rejuvenation and lightening. The authors concluded both "appear to be safe and potentially effective," but noted that very few studies compare them directly, and that more high-quality research is needed.
Many of those studies also combined the ingredients with in-office procedures like microneedling, so results from a clinic don't automatically apply to a cream. If you're curious about the clinic version, see the stem cell facial.
How do I know which one is in my product?
Check the ingredient list. Look for "conditioned media" or "conditioned medium," "exosomes" or "extracellular vesicles," or the name of a specific growth factor such as EGF. Then check whether the brand explains the source.
The bottom line
Growth factors, exosomes and conditioned media are related, not interchangeable. Know which one you're buying, check the source and keep expectations realistic. For the full picture, read our guide to stem cell skincare.
Written by the CharaOmni Team
CharaOmni was founded by Dr. Joy Kong, MD, a triple board-certified, UCLA-trained physician named Stem Cell Doctor of the Decade in 2021. Our team researches every guide using peer-reviewed studies and official health sources, so you can make informed decisions about your skin.
Sources
At CharaOmni, we take what we share seriously. Every claim in our guides is backed by real, verifiable sources: peer-reviewed research, official health authorities and established scientific institutions. We link to every source so you can read it yourself and make informed decisions about your skin.
- Jafarzadeh A, et al. Effectiveness of regenerative medicine for skin lightening and rejuvenation: a systematic review of extracellular vesicles and conditioned media. Stem Cell Research & Therapy. 2025;16:513.
This article is for educational purposes only and is not medical advice. CharaOmni is a cosmetic product and is not intended to diagnose, treat, cure or prevent any disease.