56% less visible hair fall-out in 12 weeks
A brand-run study. We report it as stated and do not repeat the number as fact.
—
Stated by brand
Only the brand’s testing shows this.
Act+Acre
Stem Cell Scalp Serum
Scalp treatment
- Scalp treatment
- serum
- Vegan · label states
Size2.2 fl oz
Price$86seen at one store · 2.2 oz
Price / oz$39.09/ozat 2.2 oz
Where to buy3 stores · $86.00–86.00
Manufacturer page: actandacre.com
Personal fit
Is this right for you?
Complete the consultation to see exactly how well this product fits your hair and your goals. With 2,400+ products in our library we can match exactly the right products to you.
- In 10 minutes we can identify your exact hair condition and traits.
- Every product matched against your hair across the 15 factors we check.
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- Your goals, scalp, damage history, water, budget, and scent preferences all shape your plan.
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Factor
Your profile
Fit
Best for hair types
All types
Not in your profile
Moisture level
High
Not in your profile
Slip / detangling
Little
Not in your profile
Silicone / wax buildup
None
Not in your profile
Clarifying wash needed
Low
Not in your profile
Parabens / preservatives
Not determined
Not in your profile
Essential oils
Not determined
Not in your profile
Vegan / cruelty-free
Vegan · label states
Not in your profile
Animal-derived ingredients
Vegan · label states
Not in your profile
Heavy humectants
Heavy
Not in your profile
Show all 15 factors we check
The rest of what your plan weighs on this product.
Hard-water defence
High
Not in your profile
UV filter
None listed
Not in your profile
Ingredient list
24 ingredientsAbout average
Not in your profile
Price tier
Prestige
Not in your profile
Where to buy it
Brand websiteOne channel
Not in your profile
The consultation builds your hair profile, then reads every factor in this table against it — and tells you where this product fits, or what to use instead.
Start your consultation$49.00 once, for your consultation and hair profile. No subscription, no required purchases.
Your avoid-list
Same job for less elsewhere
$39.09/oz at 2.2 oz — more than 95% of the 154 scalp treatments , which mostly run $3.25–20.23/oz.
Great for
Nothing in the formula stands out either way.
Maybe skip if
Dry or very humid airwhere heavy humectants work against you
Tight budgetsit sits in the upper price tiers
Picking it up locallywe have it recorded in one channel only
What the formula actually does
Read from the label, not the marketing
Each row says where it comes from: F means we derived it from this product’s own ingredient list, S means it is a claim the brand makes that the formula neither confirms nor contradicts.
Slip and detangling
Little
Nothing here is built to reduce combing force.
Oils and butters
None
No oils or butters in the list.
Water-binding (humectants)
High
Humectants near the top — water-binding is a headline mechanism here.
Needs detergent to remove
No
Nothing here needs a detergent wash to remove.
Hard-water defence
Chelators present
Chelators are present — they bind hard-water and pool minerals.
from the formula
stated by the brand
reported by reviewers
Scale: 1 dot low · 5 dots high, within this product type.
Ingredients that matter
The ingredients that change a decision
The workhorse ingredients plus anything lower down that changes a decision. These chips name what an ingredient does — they are not safety scores, and no ingredient here is rated good or bad on its own.
| Ingredient | What it does | Why it matters | Chip |
|---|---|---|---|
| WaterWater (Aqua) | solvent | The base everything else is dissolved in | Neutral |
| Glycerin | humectant | Pulls water into the hair | Moisturizes |
| Butylene Glycol | humectant | Pulls water into the hair | Moisturizes |
| Aloe Barbadensis Leaf Juice (ALOE) | — | — | Neutral |
| Bambusa Vulgaris Leaf/Stem Extract (BAMBOO) | — | — | Neutral |
| Caprylyl Glycol | preservative | Keeps the product from spoiling | Moisturizes |
| Carbomer | thickener | Adjusts the texture | Holds |
| Citric Acid | pH adjuster | Fine-tunes the pH | pH balancer |
What the list leaves out, and what it carriesHard-water chelators are present.
Full ingredient list (24)
US labelling rules put ingredients above 1% in descending order of amount; below 1% they may be listed in any order. Annotations keep three readings separate: the ingredient's general function, its role in this product type, and what its position can support.
-
1
Water
· Water (Aqua)
General function
The base of almost every rinse-off and cream hair product. It carries everything else and is normally the first ingredient on the label.
Leading ingredientListed in the first three ingredients, it is likely a structural part of this formula.
- solvent
-
2
Glycerin
General function
A small water-loving molecule that draws moisture into the hair and holds it there. It is the most common softening ingredient in conditioners and leave-ins.
Leading ingredientListed in the first three ingredients, it is likely a structural part of this formula.
Scientific ReportsMay suitDry, coarse, or high-porosity hairHigh-porosity hair loses water fast; a humectant holds some of it in place for longer than the wash itself would.
May suitVery dry or highly damaged hairBinds water into the outer layers of the strand, and water is what makes dry hair flexible again rather than brittle.
DependsClimate-sensitive or frizz-prone hairWater moves both ways. Measured across concentrations, glycerin solutions give water up in some conditions and take it from the air in others. What it does for you depends on how much of it is there and on the air around it.
- humectant
-
3
Butylene Glycol
General function
A light humectant and carrier that helps extracts dissolve.
Leading ingredientListed in the first three ingredients, it is likely a structural part of this formula.
PubChemMay suitFine or easily flattened hairLight and water-binding rather than oily, so it hydrates without contributing weight.
May suitVery dry or highly damaged hairA small water-binding solvent. It holds moisture and helps the rest of the formula spread evenly over the strand.
DependsClimate-sensitive or frizz-prone hairA humectant follows the air: it holds water in humid conditions and can give it up in very dry ones. Climate decides what it does more than the label does.
- humectant
- solvent
- 4 Aloe Barbadensis Leaf Juice (ALOE)
- 5 Bambusa Vulgaris Leaf/Stem Extract (BAMBOO)
- ▾Below about this point, order stops being meaningful — these are typically used at 1% or less.
-
6
Caprylyl Glycol
General function
A gentle preservative helper that also holds a little moisture.
Estimated lower-concentration zoneIt appears around or below the estimated 1% line, where label order no longer indicates relative amount; its role may be minor or technical.
PubChemMay suitVery dry or highly damaged hairHumectants bind water into the strand, and water — not oil — is what makes dry hair flexible instead of brittle.
DependsClimate-sensitive or frizz-prone hairA humectant follows the air: it holds water in humid conditions and can give it up in very dry ones. Climate decides what it does more than the label does.
- preservative
- humectant
-
7
Carbomer
General function
A thickener that turns a liquid into a clear gel. It also contributes a light hold.
Estimated lower-concentration zoneIt appears around or below the estimated 1% line, where label order no longer indicates relative amount; its role may be minor or technical.
May suitClimate-sensitive or frizz-prone hairA set polymer film is a physical barrier to humidity, so a style keeps its shape longer in damp conditions.
May suitMaximum-hold stylingSynthetic film formers dry into a continuous film, which is what holds a shape against movement and against humid air.
DependsBuild-up-sensitive routinesSome acrylate copolymers rinse with water and some need a detergent; the label alone does not say which one a formula used.
- thickener
- polymer
- film former
-
8
Citric Acid
General function
Used to bring the product to a slightly acidic pH, which helps the cuticle lie flat. It is almost always near the end of the list.
Estimated lower-concentration zoneIt appears around or below the estimated 1% line, where label order no longer indicates relative amount; its role may be minor or technical.
International Journal of TrichologyMay suitBuild-up-sensitive routinesHolds hard-water minerals in solution so they rinse away instead of depositing on the hair.
May suitFrizz-prone, damaged, or high-friction hairThe acid side of pH adjustment, and the reason it matters is measured: alkaline formulas raise the fibre's surface negative charge, increase friction between strands and lift the scales, while lower-pH ones do the reverse.
May suitGray, silver, or brass-prone hairWhere a warm cast comes from water minerals rather than from the hair itself, holding those metals in solution is what removes it.
- pH adjuster
- hard-water chelator
- 9 Plant-Based Collagen
-
10
Ethylhexylglycerin
General function
A preservative booster that also adds a little softness. Almost always paired with phenoxyethanol.
Estimated lower-concentration zoneIt appears around or below the estimated 1% line, where label order no longer indicates relative amount; its role may be minor or technical.
PubChemMay suitFrizz-prone, damaged, or high-friction hairEmollients fill and smooth the surface of the strand, which lowers the friction that lifts the cuticle and reads as roughness.
- preservative
- emollient
- 11 Glucosamine Hcl
-
12
Glycereth-26
General function
A glycerin derivative used as a light humectant and carrier.
Estimated lower-concentration zoneIt appears around or below the estimated 1% line, where label order no longer indicates relative amount; its role may be minor or technical.
May suitFine or easily flattened hairLight and water-binding rather than oily, so it hydrates without contributing weight.
May suitVery dry or highly damaged hairA small water-binding solvent. It holds moisture and helps the rest of the formula spread evenly over the strand.
DependsClimate-sensitive or frizz-prone hairA humectant follows the air: it holds water in humid conditions and can give it up in very dry ones. Climate decides what it does more than the label does.
- humectant
- solvent
-
13
Lecithin
General function
A soy- or sunflower-derived lipid that helps conditioning ingredients spread evenly on the strand.
Estimated lower-concentration zoneIt appears around or below the estimated 1% line, where label order no longer indicates relative amount; its role may be minor or technical.
PubChemMay suitFrizz-prone, damaged, or high-friction hairEmollients fill and smooth the surface of the strand, which lowers the friction that lifts the cuticle and reads as roughness.
- emulsifier
- emollient
- 14 Leuconostoc/Radish Root Ferment Filtrate (RADISH)
- 15 Malus Domestica Fruit Cell Culture Extract (APPLE)
-
16
Pentylene Glycol
General function
A humectant that also helps preserve the formula, often used where a brand wants a short preservative list.
Estimated lower-concentration zoneIt appears around or below the estimated 1% line, where label order no longer indicates relative amount; its role may be minor or technical.
PubChemMay suitFine or easily flattened hairLight and water-binding rather than oily, so it hydrates without contributing weight.
May suitVery dry or highly damaged hairA small water-binding solvent. It holds moisture and helps the rest of the formula spread evenly over the strand.
DependsClimate-sensitive or frizz-prone hairA humectant follows the air: it holds water in humid conditions and can give it up in very dry ones. Climate decides what it does more than the label does.
- humectant
- solvent
- preservative
-
17
Phenoxyethanol
- preservative
- 18 Pisum Sativum (Pea) Extract (PEA)
-
19
Propanediol
General function
A corn-derived humectant and solvent, often chosen as a lighter-feeling alternative to propylene glycol.
Estimated lower-concentration zoneIt appears around or below the estimated 1% line, where label order no longer indicates relative amount; its role may be minor or technical.
PubChemMay suitFine or easily flattened hairLight and water-binding rather than oily, so it hydrates without contributing weight.
May suitVery dry or highly damaged hairA small water-binding solvent. It holds moisture and helps the rest of the formula spread evenly over the strand.
DependsClimate-sensitive or frizz-prone hairA humectant follows the air: it holds water in humid conditions and can give it up in very dry ones. Climate decides what it does more than the label does.
- humectant
- solvent
- 20 Quercus Petraea Fruit Extract (OAK)
-
21
Sodium Hyaluronate
General function
A large water-binding molecule that sits on the surface holding moisture.
Estimated lower-concentration zoneIt appears around or below the estimated 1% line, where label order no longer indicates relative amount; its role may be minor or technical.
May suitDry, coarse, or high-porosity hairHigh-porosity hair loses water fast; a humectant holds some of it in place for longer than the wash itself would.
May suitVery dry or highly damaged hairBinds water into the outer layers of the strand, and water is what makes dry hair flexible again rather than brittle.
DependsClimate-sensitive or frizz-prone hairA humectant moves water in whichever direction the air allows: it holds moisture in humid conditions and can pull it back out of hair in very dry ones.
- humectant
-
22
Sodium Hydroxide
General function
A strong base used in trace amounts to raise pH; fully neutralised in the finished product.
Estimated lower-concentration zoneIt appears around or below the estimated 1% line, where label order no longer indicates relative amount; its role may be minor or technical.
International Journal of TrichologyDependsFrizz-prone, damaged, or high-friction hairThe alkali half of a pH-adjusting pair, used in small amounts to bring a formula up to its target rather than to make it alkaline. Alkaline conditions raise the fibre's surface charge and lift the scales — but the finished pH is not on the label.
- pH adjuster
-
23
Tetrasodium Glutamate Diacetate
General function
A biodegradable hard-water chelator used in place of EDTA.
Estimated lower-concentration zoneIt appears around or below the estimated 1% line, where label order no longer indicates relative amount; its role may be minor or technical.
PubChemMay suitBuild-up-sensitive routinesBinds the calcium and magnesium in hard water, which is what stops mineral deposits accumulating on the strand wash after wash.
May suitGray, silver, or brass-prone hairCopper and iron carried in tap water deposit on the strand and read as a dull, warm cast on gray or light hair. A chelator holds those metals in solution so the wash carries them off.
- hard-water chelator
-
24
Xanthan Gum
General function
A fermented sugar gum that thickens water-based formulas and adds soft, natural hold.
Estimated lower-concentration zoneIt appears around or below the estimated 1% line, where label order no longer indicates relative amount; its role may be minor or technical.
May suitCurls or waves needing flexible holdA polysaccharide film stays softer than a synthetic one as it dries, which is what leaves a curl defined but still able to move.
May suitFrizz-prone, damaged, or high-friction hairA soft film binds neighbouring strands together, which is most of what keeps flyaways lying down without stiffness.
May not suitMaximum-hold stylingGum films stay soft. A style that needs firm fixation usually wants a synthetic polymer doing the holding.
- gum
- thickener
- film former
What the whole list adds up to
- 7 humectants
- 5 solvents
- 4 preservatives
- 2 thickeners
- 2 film formers
- 2 pH adjusters
- 2 hard-water chelators
- 2 emollients
- 1 polymer
- 1 emulsifier
- 1 gum
Drug facts actives
- undefined
This product is an over-the-counter drug as well as a cosmetic. It treats a cosmetic scalp condition; it does not diagnose or treat disease.
Ingredient list captured 2026-09-05. Formulas change — check the package in your hand when an ingredient matters to you.
Price · 2.2 oz
Seen at
$86
Good value under
$29
Priced above the products that do the same job. Stores sell it above the $29 line; products that do this job typically go for about $54 at this size.
Show the price ladder
Where we’ve seen it3 listings · 3 stores
-
Act+Acre (actandacre.com)
$86.002.2 oz · $39.09/ozSep 5Lowest per oz
-
Sephora
$86.002.2 oz · $39.09/ozSep 5
-
Act+Acre
$86.002.2 oz · $39.09/ozSep 5
Sorted by price per ounce. Dated observations from our research, not live prices. Direct store pages, no affiliate links. We don’t sell this product.
How we work this out
- 2.2 oz is the size stores list most often; every comparison on this page is made at it. Other sizes are shown in the Sizes row and the store list.
- Seen at $86 is the price we have observed for the 2.2 oz. We need three stores before we call a price commonly seen.
- Good value under $29 comes from the 8 products we score as doing the same job as this one. A quarter of them cost less than $12.99/oz; at 2.2 oz that is $29. Under that line you are paying less than most of them.
- About $54 is what those same products typically cost at this size — the midpoint of their prices per ounce, scaled to 2.2 oz.
Formula
3
Formula score
3 of 10
Above the range for scalp treatments per ounce for a shorter formula — there is no conditioning agents up front — with 7 close matches costing less.
How the score is counted
- 7 products that do the same job cost less per ounce
- Costs more per ounce than 95% of the 154 scalp treatments we’ve priced
- No conditioning agents up front in the formula
- No oils or butters in the working zone either
- Conditioning agents up frontWhat makes wet hair comb through.3 pts
- Oils or butters in the working zoneSoftens the strand rather than just coating it.2 pts
- Slip for detanglingReduces the force it takes to comb wet hair.2 pts
- A humectantBinds water into the hair.1 pt
- A pH adjusterBrings the formula to the acidic pH hair prefers.1 pt
- Fragrance kept out of the top eightScent as a finishing touch, not a major share.1 pt
The formula score is completeness for the job: the share of the systems this product type is normally built around that we can find in this list, weighted. It is not efficacy, not quality, and it never compares across product types.
Does the same job, for less
Same derived functions — what it cleans, conditions, coats or holds — at a lower cost per ounce. Scent, texture and where you buy it can still differ.
Grow GorgeousClosest function
Hair Density Serum Intense
$25.00/oz $14.09/oz less
- Protein-free
- Lightweight
- Silicone-free
- Differs
Color WowClose function
Youth Juice Collagen Scalp Serum
$27.06/oz $12.03/oz less
- Fragrance-free
- Lightweight
- Silicone-free
- Function
- Also
BosleyLowest cost per oz
Revive+ Densifying Serum for Women
$24.99/oz $14.10/oz less
· Close function
- Function
- Also
See more alternatives in the product library
These are functional neighbours, not personal recommendations — they are close on formula, not chosen for anyone. Get the one that fits your hair, routine, and budget
Final decision
Should you buy it?
Hard to justify at this priceBest user
Nothing in the formula narrows this to one kind of hair.
Biggest tradeoff
Less suited to very dry or very humid climates, people shopping on a budget, or anyone who wants to pick it up locally
Best alternative if not
Grow Gorgeous Hair Density Serum Intense — for similar results at a lower price
We do not sell products or take placement fees. This page states what the formula and the prices show; the consultation is what matches it to a person.
Claims check
What the brand says, against what the formula shows
Claims are quoted from the brand. We only mark one supported, partly supported, or conflicting when the ingredient list actually speaks to it; everything else stays "stated by the brand", which is not a criticism — most claims simply cannot be read off a label.
0
SupportedBacked by ingredients
0
Partly supportedSome supporting logic
5
Stated by brandNo clear evidence
0
Potential conflictFormula works against claim
86% noticed more hair coverage on the scalp. 85% noticed more volume
A brand-run study. We report it as stated and do not repeat the number as fact.
—
Stated by brand
Only the brand’s testing shows this.
90% saw new hair growth in 6 weeks
A brand-run study. We report it as stated and do not repeat the number as fact.
—
Stated by brand
Only the brand’s testing shows this.
100% agree product increased hair thickness
A brand-run study. We report it as stated and do not repeat the number as fact.
—
Stated by brand
Only the brand’s testing shows this.
100% agree hair felt stronger + healthier
A brand-run study. We report it as stated and do not repeat the number as fact.
—
Stated by brand
Only the brand’s testing shows this.
How to read this
We look at the first 10–15 ingredients and what they do in a formula — not marketing. If the list doesn't speak to a claim, we don't assume.
Reviewers
What people report
Recurring themes our researchers wrote in their own words from sourced reviews. We do not store or scrape star ratings.
Some reviewers say their overall hair shedding and daily hair loss dropped noticeably after starting the serum
reviewers tracking shedding/hair lossReviewers also credit it with a healthier scalp overall — less itching, dryness and tightness — alongside the hair-growth effect
reviewers describing scalp feel, not just hair growthReviewers repeatedly note the texture is lightweight and does not leave hair greasy, including right at the hairline
reviewers commenting on daily applicationMultiple reviewers report visible new hair growth and thicker-looking hair after a few months of consistent use
reviewers using the serum for 3+ monthsMore from Act+Acre
How this page was made
- Everything above is generated from our researched product record — identity, the ingredient list as printed, the brand's own claims, dated price observations, and review themes written in our researchers' own words. No part of this page is written per product.
- The value band is a fixed label over two stored numbers: this product’s cost per ounce as a percentile of every product of this type we have priced, each at the size it is most often sold in, and how many products we score as doing the same job cost at least a quarter less per ounce.
- Both scores out of ten are defined on this page. The formula score is completeness for the job, computed from a fixed per-format checklist shown beneath the gauge; the price score is cost per ounce against every product of this type we have priced.
- The "Is this right for you?" panel reads only your own consultation answers, and it applies exactly the filters our recommendation engine applies. It is computed when you load the page and is never stored on it.
- 3 sources consulted for this product (1 manufacturer or regulatory, 0 retailer, 2 editorial), last checked 2026-09-05.
- Ingredient references are linked for 10 of 14 product-aware annotations on this page. Fit notes are conditional formulation guidance, not a conclusion about the finished product or about you.
- We have not tested this product in a lab and we do not physically test your hair. Formula readings come from the ingredient list; behaviour claims are labelled as the brand's.
- Ingredient order tells you relative amount only above roughly 1%. Prices are observations on the dates shown and change without notice.
- Ingredient names link to our ingredient library, where each entry shows what it does, which product types use it, and where it usually sits on a label across everything we have researched.
- This is cosmetic information, not medical advice, and nothing here diagnoses or treats a health condition.
- Formula readings: derivation v22. Record last updated 2026-09-05.