OIL
Oenothera Biennis (Evening Primrose) Oil
- oil
A light oil rich in fatty acids, used in scalp and dry-hair treatments.
- products in our library
- 40
- of researched products
- 1%
- on the label, in our co-washes
- usually #10
- most common in
- Co-wash
- in water
- Oil-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.
Where the class sits between an ester and a butter.
How much it slows water leaving the strand.
| Property | Level | Out of |
|---|---|---|
| Buildup risk | Needs a cleanser | 4 of 5 |
| Rinse-out behaviour | Rinses with a cleanser | 2 of 5 |
| Weight | Rich | 4 of 5 |
| Sealing | Strong | 4 of 5 |
What it does for a formula
What Oenothera Biennis (Evening Primrose) Oil does
The general function first, then how the role changes by product type where we have researched it.
Coats the surface and makes hair feel more pliable.
Sits on the outside of the cuticle and holds moisture in.
Smooths the feel of the strand without adding hold or cleaning.
It takes a surfactant to remove — worth knowing on a low-detergent routine.
Charge
Charge is not recorded for this ingredient.
Solubility
Needs a surfactant to remove. On a low-detergent routine it can build up over time.
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 ? |
|---|---|---|
Co-wash
6 products
|
secondary · #10 | |
Conditioner
6 products
|
secondary · #15 | |
Leave-in
6 products
|
secondary · #15 | |
Mask / treatment
5 products
|
secondary · #18 | |
Finisher: oil
4 products
|
secondary · #10 | |
Scalp treatment
4 products
|
secondary · #17 | |
Shampoo
4 products
|
secondary · #19 | |
Finisher: shine spray
1 product
|
secondary · #12 | |
Styler: curl cream
1 product
|
secondary · #11 | |
Styler: paste
1 product
|
secondary · #13 |
2 more product types
| Product type | How common | Typical position on label ? |
|---|---|---|
Styler: smoothing cream
1 product
|
supporting · #8 | |
Styler: texture spray
1 product
|
secondary · #9 |
| Product type | Products | Share of category | Median position | Earliest position | Band |
|---|---|---|---|---|---|
| Co-wash | 6 | 6% | 10 | 10 | secondary |
| Conditioner | 6 | 1% | 15 | 8 | secondary |
| Leave-in | 6 | 1% | 15 | 8 | secondary |
| Mask / treatment | 5 | 1% | 18 | 16 | secondary |
| Finisher: oil | 4 | 2% | 10 | 8 | secondary |
| Scalp treatment | 4 | 3% | 17 | 14 | secondary |
| Shampoo | 4 | 0% | 19 | 17 | secondary |
| Finisher: shine spray | 1 | 2% | 12 | 12 | secondary |
| Styler: curl cream | 1 | 1% | 11 | 11 | secondary |
| Styler: paste | 1 | 1% | 13 | 13 | secondary |
| Styler: smoothing cream | 1 | 2% | 8 | 8 | supporting |
| Styler: texture spray | 1 | 2% | 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 | 5 |
| 9-15 | Secondary | 18 |
| 16-25 | Lower | 21 |
| 26+ | Trace | 1 |
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
Conditional formulation guidance, scoped to a hair condition and to the positions where it is meaningful. It is not a conclusion about any finished product, and not a conclusion about you.
Coats the surface and slows water leaving the strand, which is usually what coarse hair that dries out fast is missing.
A thin oil layer lowers friction between strands and flattens the raised cuticle that scatters light and catches on its neighbours.
Near the top of a list an oil is weight before it is anything else, and fine hair shows that first at the roots.
Read where it is listed in the first three ingredients or positions 4–8.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 this ingredient is evidence of, what it is not evidence of, and what our own method can and cannot tell you.
- softness and shine
- a softer feel
- something that lasts through the day
- moisture that stays on coarse or porous hair
- 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 oil, listed below the main ingredients in our co-washes
- it was on the label of every product we counted — we read printed ingredient lists, not marketing copy
- 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.
- Tocopherol · 21
- Tocopheryl Acetate · 14
- Aloe Barbadensis Leaf Juice · 14
- Mentha Piperita (Peppermint) Oil · 13
- Stearyl Alcohol · 13
- Cetrimonium Chloride · 13
- Simmondsia Chinensis (Jojoba) Seed Oil · 12
- Helianthus Annuus (Sunflower) Seed Oil · 12
- Cetyl Alcohol · 12
- Benzyl Alcohol · 12
The number beside a name is how many products in our library list both.
These ingredients tend to appear together to deliver a stated effect, give the formula body and hold, 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.
L'anza · Styler
Healing Style Smoother Balm
#8 on the label · $4.71/oz
Ouai · Leave-in
Leave In Conditioner - North Bondi
#8 on the label · $5.33/oz
Ouai · Leave-in
Leave In Conditioner Melrose Place
#8 on the label · $5.33/oz
Ouai · Conditioner
St. Barts Conditioning Detangling and Frizz Fighting Leave Conditioner
#8 on the label · $5.33/oz
Aunt Jackie's · Finisher
Batana, Jojoba & Rice Elixir Hair and Scalp Oil
#9 on the label · $4.70/oz
Hairstory · Finisher
Nourishing Hair Oil
#9 on the label · $18.50/oz
Sexy Hair · Styler
Style Sexy Hair Play Dirty Dry Wax Spray
#9 on the label · $4.78/oz
Hairstory · Co-wash
New Wash Deep Clean
#10 on the label · $6.50/oz
Hairstory · Co-wash
New Wash Original
#10 on the label · $7.31/oz
Hairstory · Co-wash
New Wash Original Fragrance-Free
#10 on the label · $6.00/oz
Hairstory · Co-wash
New Wash Rich
#10 on the label · $6.00/oz
See all 40 products in the library that list Oenothera Biennis (Evening Primrose) Oil
Identity
What this entry is, and what our references call it.
No public-domain structure depiction is available for this entry.
Oenothera Biennis (Evening Primrose) Oil
- emollient
- evening primrose oil
- oenothera biennis (evening primrose) oil
- oenothera biennis oil
For your hair?
Whether Oenothera Biennis (Evening Primrose) Oil matters for your hair depends on your hair.
40 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 — 40 of 3889 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.