Growth Factors in Skincare: What They Are, How They Work, and Why Your Esthetician Uses Them
Ever stood in front of a shelf of serums that all promise growth factors and wondered what you're actually buying? We perform ProCell microchanneling at Mysa Day Spa in West Portal, San Francisco, so we get this question often. Here is the plain version, including the parts labels leave out.
The short version
- Growth factors are signaling proteins your skin cells already make to coordinate repair and renewal. Skin makes fewer of them as you age.
- Most growth factor molecules are large, and your skin's outer layer is built to keep large molecules out. A serum on intact skin often does less than the label implies.
- The evidence is real but modest. Some controlled studies show improvement with consistent use, but many are small or funded by the makers.
- "Stem cell" on a label is often a plant extract, which does not speak to human skin cells. Human-derived growth factors are a different category.
- At Mysa we pair growth factor serums with ProCell microchanneling, because tiny channels are how a serum reaches the layer where repair happens. It is not right for everyone, and we will say so.
The Basics
What are growth factors in skincare?
Growth factors are proteins that act as chemical messengers between cells. Your skin's own cells make them, telling neighbors when to divide, when to build collagen, and when to stop once a repair is done. Levels in the skin peak in youth and decline from there.
In skincare, the term covers serums and treatments that supply these messengers from an outside source, with the aim of nudging aging skin back toward repair mode. The same cut that closes in three days at twenty can take a week at fifty. The signal is still there, just quieter.
The Players
What growth factors do for your skin
Different growth factors have different jobs. These are the ones you will see named most often.
EGF (epidermal growth factor): surface repair
EGF acts on the skin's outer layer. It signals new surface cells during healing, which is why it appears in products aimed at texture and renewal.
FGF (fibroblast growth factors): rebuilding structure
FGFs act on fibroblasts, the cells in the dermis that build collagen and elastin. They are tied to tissue repair, so they show up in products aimed at firmness.
TGF-beta and IGF-1: collagen signals
TGF-beta is one of the main signals that stimulates type I and type III collagen and the supporting matrix around it. IGF-1 is believed to support cell growth more broadly. Both turn up in "multi-factor" serums.
Why production slows
Skin levels of growth factors fall with age, and sun exposure adds damage on top. Topical growth factors are an attempt to replace some of what is missing.
Sourcing
Where growth factors come from, and why the label matters
Not every growth factor product is made the same way, and the source changes what you are getting.
| Source | What it actually is | Evidence so far | Where you see it |
|---|---|---|---|
| Human cell-conditioned media | Lab-grown human cells release growth factors into a liquid. The liquid is kept and the cells are filtered out. | Strongest of the topical types, but studies are mostly small and often maker-funded. | Professional serums such as ProCell; some retail lines such as SkinMedica |
| Recombinant (bioengineered) | One growth factor, such as EGF, made by yeast or bacteria engineered to produce the human protein. | Consistent and easy to standardize. Usually one or a few factors, and independent data varies. | Many retail serums. Check the ingredient list. |
| Animal-derived | Filtrate of snail secretions, among others. | One small controlled study showed improvement in sun-damaged skin. | A few specialty brands |
| Plant "stem cell" extract | An extract from plant cells. Not human growth factors. | No significant data showing it activates growth in human skin. | Many creams labeled "stem cell" |
| Platelet-rich plasma (PRP) | Growth factors from your own blood, concentrated and injected by a medical provider. | Early evidence. Results vary with how the plasma is prepared. | Medical offices. Not a facial, and not something we offer. |
Human cell-conditioned media
Lab-grown human cells release growth factors and other signaling proteins into a liquid. The cells are filtered out, so the bottle holds what the cells secreted, not the cells themselves. Most of the better-studied topical products use this approach. ProCell, the maker of the microchanneling system we use, is described in the trade publication DERMASCOPE as making its serums from human stem cells taken from adult bone marrow donors. After a set incubation time, the cells are filtered out of the broth they grew in, leaving the growth factor proteins.
Recombinant growth factors
Bacteria or yeast are engineered to make a single human growth factor. It is consistent and easy to standardize, but it is usually one or a few factors, not the full mix a living cell releases. Whether that matters in skin is still being studied.
Plant "stem cells"
Plant stem cell extracts are the most marketed and least convincing. Plant cells do not make human growth factors, and dermatology reviews have found no significant data that they activate cell growth in human skin. They may offer ordinary antioxidant benefits, which is a different job. When you see "stem cell" on a label, check whether it says human-derived or plant-derived.
PRP
Platelet-rich plasma uses growth factors from your own blood, injected by a medical provider. It is a separate procedure from a growth factor facial, and we do not offer it.
The Evidence
Do growth factor serums actually work?
Some do, modestly, with consistent use. Two dermatologists who reviewed the research in 2014 found a limited number of controlled studies in which topical growth factors increased collagen and thickened the skin's surface layer, though many studies were small. A 24-week, vehicle-controlled trial published in 2023 found that a serum made from human fibroblast conditioned media reduced sagging, lines, and hyperpigmentation more than a placebo. Its authors were affiliated with the product's makers, which is common in this field and worth knowing.
The takeaway: a plausible, studied ingredient, not a miracle. Expect weeks of daily use and gains in texture, tone, and fine lines, not a substitute for injectables. Price is a poor guide. Check the source and whether the maker has published controlled data.
Delivery
The delivery problem: why microchanneling changes the math
Here is the part most product pages skip. Growth factors are big molecules, over 15,000 daltons. Water-soluble molecules above roughly 500 daltons barely cross intact skin. The same dermatology review concluded that growth factors are unlikely to penetrate intact skin in meaningful amounts.
Think of your skin as a building with a locked front door. A serum on intact skin is a package left on the doorstep. Microchanneling installs thousands of tiny mail slots, so the package goes inside, to the layer where repair actually happens.
A handpiece with very fine, sterile tips creates thousands of microscopic channels in the upper layer of skin. The channels close on their own within hours, but opening them starts the skin's own repair response. We apply a growth factor serum while they are open.
What happens in the MicroGlow room
The Mysa MicroGlow Renewal Facial is a 60-minute appointment, performed by a licensed esthetician. Here is the sequence:
Cleanse the treatment area.
Apply topical numbing, which sits for about 20 minutes. We use that time for a neck and shoulder massage.
Disinfect the area right before we start.
Microchannel in sections, with depth set for your skin and the area being treated. Growth factor serum goes on as we work.
Apply a hydrating mask with LED light to settle the skin.
Finish with calming and protective products chosen for your skin.
What does it feel like? Most clients describe a light vibration or scratching once the numbing has set in. A few say it feels like a lot of tiny bug bites and is not enjoyable. You leave pink and warm, closer to an hour of sun than a burn, and mineral makeup is fine from two hours afterward. Our day-by-day guide covers the rest: microchanneling aftercare, day by day.
The delivery logic is sound biology, but we are not aware of independent research isolating how much the serum adds on top of the channeling itself. Microchanneling triggers a repair response on its own. The serum is there to support it.
Routine Building
Growth factors, retinoids, and peptides: how to use them together
Three ingredient families, three jobs. Retinoids speed up cell turnover and are well proven, but can irritate. Peptides are short amino acid chains, and some act as signals. Growth factors are the full signaling proteins covered above.
Our rule is simple: one active job per step, and introduce one new active at a time. A basic order looks like this:
Cleanse.
Apply your growth factor or peptide serum to clean skin and let it absorb.
Moisturize.
In the morning, finish with broad-spectrum sunscreen.
If you use a retinoid, keep it to its own nights rather than stacking everything at once.
After a MicroGlow treatment the rules tighten: no retinol, AHAs, BHAs, or vitamin C for at least one week, then reintroduce one at a time. For daily maintenance, our estheticians recommend Jan Marini, especially their peptide complexes.
Safety
Are growth factors safe?
Can growth factors in skincare cause cancer? There is no evidence that topical or cosmetic growth factor products do. The question comes up because growth factors regulate cell growth, and lab studies of single growth factors in isolation have shown mixed results. The 2014 dermatology review found no studies of sufficient quality showing that topical growth factors either promote or prevent cancer in people. A preliminary lab study of cosmetic growth factor products found no effect on melanoma cell growth. Long-term, high-quality human data is still limited, and we would rather say so.
Any topical product can cause irritation or an allergic reaction. With a history of skin cancer or during cancer treatment, ask your doctor first. We do not perform microchanneling during chemotherapy or radiation.
We also screen for timing. MicroGlow is not the right treatment right now if you have:
- Pregnancy or nursing
- An active breakout, cold sore, or open or infected skin
- An eczema, psoriasis, or rosacea flare in the treatment area
- Sunburned skin
- Isotretinoin (Accutane) use in the past six months
- A history of keloid scarring
- A bleeding disorder, or blood thinners
Expectations
Who benefits most
Growth factor treatments tend to suit people who notice fine lines, uneven texture, dullness, sun damage, or early loss of firmness. In our treatment room, fine lines respond fastest, often after one to three sessions. Acne scarring usually takes more sessions, and hyperpigmentation is the slowest to improve. People who find retinoids too irritating sometimes try growth factor serums as a gentler option, though direct comparisons are limited.
It will not fix deep ice-pick scars or significant sagging, and one session is a glow, not a transformation. Our MicroGlow Renewal Facial page has a realistic timeline, and our guide to the best facial for aging skin in San Francisco compares options if microchanneling is not your fit.
FAQ
Frequently Asked Questions
Do growth factor serums actually work?
Modestly, with consistent use. Controlled studies show improvement over weeks, but many are small or maker-funded. Expect gradual change.
What is the best growth factor for skin?
There is no single winner. EGF supports surface renewal, while FGF and TGF-beta support structure and collagen. The factors likely work best in combination.
Are growth factors the same as stem cells? What about a stem cell facial?
No. Live stem cells are not used in cosmetic products. A so-called stem cell facial uses what stem cells released, such as conditioned media, or a plant extract. Check which one the label means.
Are peptides growth factors?
No. Peptides are short chains of amino acids. Growth factors are full signaling proteins. They can work well together, but they are different ingredients.
Can growth factors in skincare cause cancer?
There is no evidence that they do, though long-term human data is limited. With a history of skin cancer, ask your doctor first.
Is a growth factor injection the same as a growth factor facial?
No. Injections, such as PRP, are medical procedures. The MicroGlow Renewal Facial uses no neurotoxins, no fillers, and no injections. It is performed by a licensed esthetician.
Which is better for mature skin, growth factors or retinol?
Different jobs. Retinoids speed turnover and are well proven. Growth factors send repair signals and tend to be gentler. Many people use both, introduced one at a time.
How soon will I see results?
After microchanneling, expect mild redness and tighter-feeling skin in the first few days. Texture and tone start to shift around weeks two to four, and collagen matures over weeks six to twelve. A series matters more than one session. We recommend three sessions about four weeks apart, then maintenance every six to eight weeks.
Experience growth factors the way they work best
Curious about microchanneling? Start with our MicroGlow Renewal Facial page or book a visit. The session is 60 minutes and $398, with numbing, serums, the hydrating mask, and finishing products included.
First time with us? A consultation comes first. Before your first session we look at your skin in person and go through your history, so we can confirm the treatment suits you and set the right depth. If it is not the right fit, we will say so. If you want results with no downtime at all, a HydraFacial is the gentler route.
Mysa Day Spa, 339A W Portal Ave, San Francisco, CA 94127. Call (415) 742-5491 to book.
Call (415) 742-5491Sources
- Fabi S, Sundaram H. The potential of topical and injectable growth factors and cytokines for skin rejuvenation. Facial Plast Surg. 2014;30:157-171. https://doi.org/10.1055/s-0034-1372423
- Naughton GK et al. Targeting multiple hallmarks of skin aging: preclinical and clinical efficacy of a novel growth factor-based skin care serum. Dermatol Ther (Heidelb). 2023;13(1):169-186. https://pubmed.ncbi.nlm.nih.gov/36374431/
- Dieamant G et al. In vitro evaluation of the safety profile of cosmeceuticals containing growth factors and their analogues. Surg Cosmet Dermatol. 2012;4(3):229-236. https://repositorio.unesp.br/items/3ef25c8f-483b-4ac7-931b-46e6d516bc2e
- MDedge (Cutis). Regenerative medicine in cosmetic dermatology (plant stem cells section). https://www.mdedge.com/cutis/article/155683/aesthetic-dermatology/regenerative-medicine-cosmetic-dermatology
- DERMASCOPE. That's Not My Name: Microchanneling & Growth Factor Serums. https://dermascope.com/blogs/13816-that-s-not-my-name-microchanneling-growth-factor-serums
This article is educational and is not medical advice. Mysa estheticians are not doctors. If you have a medical condition or take medication, check with your doctor before any skin treatment.
