HUMECTANT
Zinc PCA
- humectant
A zinc salt of a natural moisturising factor, used on the scalp for oil-control and soothing claims.
- products in our library
- 74
- of researched products
- 1%
- on the label, in our shampoos
- usually #17
- most common in
- Shampoo
- in water
- Water-soluble
At a glance
Four things worth knowing about how this ingredient behaves on hair.
How much of it is left on hair between washes.
What it takes to get it off the hair again.
How strongly the class holds on to water.
The strongest binders are the ones the weather moves most.
| Property | Level | Out of |
|---|---|---|
| Buildup risk | Low | 1 of 5 |
| Rinse-out behaviour | Rinses clean | 5 of 5 |
| Water-binding | Strongest | 5 of 5 |
| Humidity sensitivity | Swings with the air | 5 of 5 |
What it does for a formula
What Zinc PCA does
The general function first, then how the role changes by product type where we have researched it.
Binds water and holds it against the hair rather than adding oil.
What a humectant does depends on the air around it as much as on the formula.
Named on the label for a specific purpose rather than for texture.
Water alone removes it, so it does not accumulate between washes.
Charge
Charge is not recorded for this ingredient.
Solubility
Rinses out with water alone, so it does not build up on hair between washes.
Where it appears
Where it appears
One row per product category in our library: how many products list it, what share of that category that is, and where it typically sits on the label.
| Product type | How common | Typical position on label ? |
|---|---|---|
Shampoo
19 products
|
secondary · #17 | |
Scalp treatment
14 products
|
secondary · #14 | |
Conditioner
12 products
|
secondary · #20 | |
Leave-in
6 products
|
secondary · #19 | |
Mask / treatment
3 products
|
secondary · #23 | |
Styler: hairspray
3 products
|
secondary · #15 | |
Styler: paste
3 products
|
secondary · #20 | |
Styler: volumizer
3 products
|
secondary · #15 | |
Styler: smoothing cream
2 products
|
secondary · #23 | |
Styler: texture spray
2 products
|
secondary · #18 |
7 more product types
| Product type | How common | Typical position on label ? |
|---|---|---|
Dry shampoo
1 product
|
secondary · #16 | |
Finisher: anti frizz finish
1 product
|
secondary · #25 | |
Finisher: serum
1 product
|
secondary · #15 | |
Finisher: shine spray
1 product
|
secondary · #21 | |
Heat protectant
1 product
|
secondary · #14 | |
Styler: curl cream
1 product
|
secondary · #19 | |
Styler: mousse
1 product
|
secondary · #13 |
| Product type | Products | Share of category | Median position | Earliest position | Band |
|---|---|---|---|---|---|
| Shampoo | 19 | 1% | 17 | 4 | secondary |
| Scalp treatment | 14 | 5% | 14 | 8 | secondary |
| Conditioner | 12 | 1% | 20 | 7 | secondary |
| Leave-in | 6 | 1% | 19 | 14 | secondary |
| Mask / treatment | 3 | 1% | 23 | 20 | secondary |
| Styler: hairspray | 3 | 1% | 15 | 10 | secondary |
| Styler: paste | 3 | 2% | 20 | 20 | secondary |
| Styler: volumizer | 3 | 2% | 15 | 14 | secondary |
| Styler: smoothing cream | 2 | 2% | 23 | 13 | secondary |
| Styler: texture spray | 2 | 2% | 18 | 17 | secondary |
| Dry shampoo | 1 | 1% | 16 | 16 | secondary |
| Finisher: anti frizz finish | 1 | 3% | 25 | 25 | secondary |
| Finisher: serum | 1 | 1% | 15 | 15 | secondary |
| Finisher: shine spray | 1 | 1% | 21 | 21 | secondary |
| Heat protectant | 1 | 0% | 14 | 14 | secondary |
| Styler: curl cream | 1 | 0% | 19 | 19 | secondary |
| Styler: mousse | 1 | 0% | 13 | 13 | secondary |
We have not researched differences by product type yet. The reading below comes from where it sits on the labels in our library.
Position footprint
Every listing in our library, by position on the label.
| Positions | Zone | Listings |
|---|---|---|
| 1-3 | Leading | 0 |
| 4-8 | Supporting | 4 |
| 9-15 | Secondary | 24 |
| 16-25 | Lower | 42 |
| 26+ | Trace | 4 |
How to read this
US labelling rules put ingredients above 1% in descending order of amount; below 1% they may be listed in any order.
So position tells you about relative amount only above that line, and we never convert a position into a percentage.
Who should pay attention
Formulation guidance for specific hair conditions, limited to the label positions where it applies. It is not a conclusion about any finished product, or about you.
High-porosity hair loses water fast; a humectant holds some of it in place for longer than the wash itself would.
Binds water into the outer layers of the strand, and water is what makes dry hair flexible again rather than brittle.
A 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.
Read from this ingredient’s chemical class. Where we have researched the ingredient itself, that reading replaces the class one.
Why it matters to shoppers
What seeing this ingredient tells you, what it does not, and the limits of our own method.
- hydration that does not add oil
- hydration rather than oil
- an ingredient included for a stated purpose
- a rinse-clean feel
- an exact safety score (we do not publish one for any ingredient)
- how a finished product performs, which depends on the whole formula, not one line of it
- the exact percentage in a bottle, because label position never converts into a number
- a secondary humectant, listed below the main ingredients in our shampoos
- it was on the printed ingredient list of every product we counted (we read labels, not marketing copy)
- frizz in every climate (what it does depends on the air)
- that a product is right or wrong for you
We do not publish safety scores or hazard grades. Where a regulator has published a restriction or a use condition, we state it and cite it; otherwise we describe what the ingredient does and stop.
Commonly paired with
The ingredients that most often appear alongside this one in our library. We leave out the near-universal ones, because they pair with everything and tell you nothing.
- Sodium PCA · 43
- Hydrolyzed Pea Protein · 42
- Hydrolyzed Vegetable Protein · 39
- Alcohol Denat. · 33
- Caprylyl Glycol · 32
- Dimethiconol Meadowfoamate · 31
- Tocopherol · 31
- Ethylhexylglycerin · 31
- Squalane · 29
- Ethylhexyl Olivate · 25
The number beside a name is how many products in our library list both.
These ingredients tend to appear together to hold on to water, firm up damaged areas, and carry the formula and let it dry.
Found in these products
The most prominent placements first. The badge is the position on that product’s own ingredient list.
Bumble and bumble · Shampoo
Seaweed Oil Control Shampoo
#4 on the label · $4.47/oz
Raw Sugar · Shampoo
The Grow Pro Shampoo - Passion Fruit + Marula
#5 on the label · $0.64/oz
Raw Sugar · Conditioner
The Grow Pro Conditioner – Passion Fruit + Marula
#7 on the label · $0.64/oz
Vegamour · Scalp treatment
GRO Scalp Detoxifying Serum
#8 on the label
Dove · Shampoo
Men Care Hydration 2 In 1 Shampoo
#9 on the label · $0.57/oz
Dove · Shampoo
Men Care Thick Full 2 In 1 Shampoo
#9 on the label · $0.61/oz
Vegamour · Scalp treatment
Scalp Clarifying Treatment
#9 on the label · $7.60/oz
Bumble and bumble · Styler
Seaweed Oil Control Styling Primer - 6.7 oz
#10 on the label · $5.37/oz
Dove · Shampoo
Men Care Pure Fresh 2 In 1 Shampoo
#10 on the label · $0.86/oz
Overtone · Scalp treatment
The Revitalizer: Hair Growth & Fortifying Elixir
#10 on the label · $4.49/oz
Aveda · Scalp treatment
Scalp Solutions Exfoliating Scalp Treatment
#11 on the label · $10.60/oz
Paul Mitchell · Scalp treatment
Clean Beauty Scalp Therapy Drops
#11 on the label · $14.45/oz
Identity
What this entry is, and what our references call it.
No public-domain structure depiction is available for this entry.
Zinc PCA
- active
- zinc pca
For your hair?
Whether Zinc PCA matters for your hair depends on your hair.
74 products in our library list itWhat this ingredient does, and where it sits on the labels we have researched.
A verdict on any product that contains it, and never a safety grade.
We do not physically test your hair. Everything above comes from the ingredient lists in our library and from published references. The consultation is what turns it into a plan.
References
Seed entry, sourcing in progress Written from our reference work; primary sourcing is still being attached.
No published source is attached to this entry yet.
How this page was made
- Every number above is counted from the ingredient lists in our own product library: 74 of 6816 researched products list this ingredient. Nothing on this page is written per ingredient.
- The dots are levels, not scores. Each one comes from what kind of ingredient it is (its chemical class, charge and solubility) or from where it sits on the labels we have.
- US labelling rules put ingredients above 1% in descending order of amount; below 1% they may be listed in any order. Position tells you about relative amount only above that line, and we never convert a position into a percentage.
- The prominence bands (leading, supporting, secondary) are the same ones the product pages use to read a single label, applied here to the median position across a category.
- We do not publish safety scores or hazard grades. Where a regulator has published a restriction or a use condition, we state it and cite it; otherwise we describe what the ingredient does and stop.
- Identifiers and references appear only when a published source is attached to this entry. Without one, we leave the row out rather than fill it in.
- This is cosmetic information, not medical advice, and nothing here diagnoses or treats a health condition.
- Entry last updated 2026-09-22. Product-page methodology: the product library.
