PRESERVATIVE
Sodium Sulfite
- preservative
A reducing agent used to keep a formula from discolouring.
- products in our library
- 30
- of researched products
- 0.8%
- on the label, in our leave-ins
- usually #38
- most common in
- Leave-in
- in water
- Water-soluble
At a glance
Four named levels, read from this ingredient’s chemical class, its charge, its solubility, or where it sits on the labels we have. More dots means more of the property named — never “better”.
How much of it is left on hair between washes.
What it takes to get it off the hair again.
What it is in the formula to protect.
Where it sits on the labels we have, in the category it appears in most.
| Property | Level | Out of |
|---|---|---|
| Buildup risk | Low | 1 of 5 |
| Rinse-out behaviour | Rinses clean | 5 of 5 |
| Role | Keeps water-based formulas | 4 of 5 |
| Prominence | Secondary | 2 of 5 |
What it does for a formula
What Sodium Sulfite does
The general function first, then how the role changes by product type where we have researched it.
Protects the oils in the bottle rather than the hair.
Anything with water in it needs one, over the life of the bottle.
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 — it does not accumulate 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 ? |
|---|---|---|
Leave-in
8 products
|
secondary · #38 | |
Shampoo
6 products
|
secondary · #32 | |
Conditioner
4 products
|
secondary · #29 | |
Styler: gel
4 products
|
secondary · #30 | |
Mask / treatment
2 products
|
secondary · #22 | |
Scalp treatment
2 products
|
secondary · #21 | |
Styler: curl cream
2 products
|
secondary · #44 | |
Styler: edge control
1 product
|
secondary · #23 | |
Styler: mousse
1 product
|
secondary · #9 |
| Product type | Products | Share of category | Median position | Earliest position | Band |
|---|---|---|---|---|---|
| Leave-in | 8 | 2% | 38 | 19 | secondary |
| Shampoo | 6 | 1% | 32 | 18 | secondary |
| Conditioner | 4 | 1% | 29 | 25 | secondary |
| Styler: gel | 4 | 3% | 30 | 30 | secondary |
| Mask / treatment | 2 | 1% | 22 | 18 | secondary |
| Scalp treatment | 2 | 1% | 21 | 18 | secondary |
| Styler: curl cream | 2 | 2% | 44 | 37 | secondary |
| Styler: edge control | 1 | 6% | 23 | 23 | secondary |
| Styler: mousse | 1 | 1% | 9 | 9 | secondary |
No product-type differences have been researched yet — the reading below is computed 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 | 0 |
| 9-15 | Secondary | 1 |
| 16-25 | Lower | 8 |
| 26+ | Trace | 22 |
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.
Why it matters to shoppers
What this ingredient is evidence of, what it is not evidence of, and what our own method can and cannot tell you.
- oils that do not turn rancid in the bottle
- a product that keeps over its shelf life
- a rinse-clean feel
- an exact safety score — we do not publish one, for any ingredient
- how a finished product performs by itself — that is the whole formula, not one line of it
- the exact percentage in a bottle — label position never converts into a number
- a secondary antioxidant, listed below the main ingredients in our leave-ins
- it was on the label of every product we counted — we read printed ingredient lists, not marketing copy
- that the product would be better without one
- 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
Ingredients that appear alongside this one most often in our library. Near-universal ingredients are excluded — they pair with everything and tell you nothing.
- Aloe Barbadensis Leaf Juice · 20
- Benzyl Alcohol · 17
- Hexyl Cinnamal · 16
- Polyquaternium-10 · 14
- Butyrospermum Parkii (Shea) Butter · 14
- Cocos Nucifera (Coconut) Oil · 13
- Disodium EDTA · 11
- Aloe Barbadensis Leaf Extract · 10
- Argania Spinosa Kernel Oil · 10
- Geraniol · 10
The number beside a name is how many products in our library list both.
These ingredients tend to appear together to give the formula body and hold, carry the formula and let it dry, and give it a scent.
Found in these products
The most prominent placements first. The badge is the position on that product’s own ingredient list.
Paul Mitchell · Styler
Foaming Pomade
#9 on the label · $3.53/oz
Nioxin · Shampoo
Scalp Relief Shampoo
#18 on the label · $3.99/oz
TGIN · Scalp treatment
Balance Collection Scalp Serum
#18 on the label
Wella Professionals · Mask / treatment
Elements Renewing Mask
#18 on the label · $5.13/oz
Pattern · Leave-in
Detangling Nectar
#19 on the label · $3.21/oz
Nioxin · Scalp treatment
Scalp Relief Treatment
#23 on the label · $11.83/oz
PATTERN · Styler
Edge Control
#23 on the label · $3.50/oz
CHI · Mask / treatment
Naturals With Aloe Vera Intensive Hydrating Hair Masque
#25 on the label · $2.52/oz
Nioxin · Conditioner
Scalp Relief Conditioner
#25 on the label · $1.86/oz
Aunt Jackie's · Shampoo
Power Wash Intense Moisture Clarifying Shampoo
#27 on the label
Aunt Jackie's · Conditioner
Soft & Sassy Super Duper Softening Conditioner
#27 on the label
Cantu · Leave-in
Ultra Moisture Nourishing Leave-In Conditioner with Batana Oil Jamaican Black Castor Oil
#27 on the label · $0.87/oz
Identity
What this entry is, and what our references call it.
No public-domain structure depiction is available for this entry.
Sodium Sulfite
- antioxidant
- sodium sulfite
For your hair?
Whether Sodium Sulfite matters for your hair depends on your hair.
30 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 is read 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 — 30 of 3928 researched products list this ingredient. Nothing on this page is written per ingredient.
- The dots are named levels read from an ingredient’s chemical class, charge, solubility, or where it sits on the labels we have — never a score.
- 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; where none is, the row is simply absent rather than filled in.
- This is cosmetic information, not medical advice, and nothing here diagnoses or treats a health condition.
- Entry last updated 2026-08-28. Product-page methodology: the product library.