Claim 01 / Rosemary oil
Regrows hair as well as minoxidil.
One 2015 trial in men with pattern hair loss found rosemary oil matched 2% minoxidil at six months. It is a single, modest-quality study — promising, not settled.
See research
Wildroot Co.
Rosemary Mint Scalp Growth Oil
Haircare
Does it live up to its claims?
Evi Evidence
Promising
5 relevant studies reviewed
- Exact product evidence · None recorded
- No study of this exact product is recorded in Evi's review.
- Ingredient evidence · 5 studies
- Rosemary oil, Peppermint oil, Castor oil have published research, but that does not necessarily establish that this exact formulation produces the same result.
- Claim-level / category evidence · None recorded
- No separate category or mechanism research is recorded for this report.
Review date not recorded
Report details / 01
What is it?
The hair-growth oil of the year, fuelled by 90-day before-and-after videos.
- Category
- Haircare
- Notable ingredients
- Rosemary oil, Peppermint oil, Castor oil
Claims audit / 02
What does it claim?
Each claim is rated separately. Ingredient evidence does not prove that this finished product produces the same result.
Promising
Claim 02 / Peppermint oil
Boosts follicle blood flow for faster growth.
The famous result is a mouse study. The tingle you feel is a cold-receptor trick, not proof of circulation change in humans.
See researchClaim 03 / Castor oil
Thickens and lengthens hair.
No human trials support growth. It coats strands so hair looks glossier and heavier, and heavy use is linked to matting in some case reports.
See researchEvidence review / 03
What does the evidence say?
Evi rates the research behind each claim. Unless an exact-product study is recorded, ingredient findings describe the ingredient—not proof that this finished formula produces the same result.
What we found
- 01
There is exactly one human study behind the viral claim, and it compared rosemary oil to a weak version of the standard drug. It was encouraging, but one study is a starting point, not a verdict.
- 02
The mint tingle feels like something is happening. It isn't evidence — mint triggers the same nerve receptors as cold water.
- 03
Castor oil doesn't grow hair. It makes hair look shinier and less frizzy, which is exactly what a 90-day video would capture anyway.
- 04
Most before-and-afters also involve better lighting, a fresh haircut and three months of not heat-styling. That's a lot of free variables.
Evidence profile
What's in it, and how direct is the evidence?
What's in it
Rosemary oil
botanical · fragrance, scalp-care
Peppermint oil
botanical · fragrance, cooling
Castor oil
emollient · emollient
How direct is the evidence?
- Exact product evidence
- — Ingredient-level evidence (this product)
- Category-level evidence
- No meaningful evidence located
How the rating was reached
Promising
Evi never assigns numeric scores. The level follows fixed rules from recorded research, so the same evidence always gives the same result.
- Quality
- 1 human trialSystematic reviews and meta-analyses rank above trials, then lab and animal work.
- Quantity
- 5 unique sourcesCounted once per source, however many claims cite it.
- Directness
- Ingredient-level evidenceExact-product studies count above ingredient or category research.
- Replication
- Not replicated in Evi's recordOne study alone cannot support a Strong level.
- Relevance to claims
- 3 of 3 claims have matched researchOnly research matched to a specific claim is counted.
- Finished product vs ingredient
- Ingredient only — not proof for this formulaIngredient research never establishes that this formulation works.
Independent summary
The Evi Take
Cheap and low risk. Reasonable to try for six months, but if you're treating real hair loss, see a doctor rather than relying on this.
An evidence-focused interpretation—not a diagnosis or personalized medical treatment advice.
What changed
- — Study summary corrected: Rosemary oil. A source-by-source audit found the previous summary said more than, or something different from, what the study itself reports. Before and after
- — Study summary corrected: Castor oil. A source-by-source audit found the previous summary said more than, or something different from, what the study itself reports. Before and after
Source library / 04
Receipts
Peer-reviewed sources reviewed for this report. Study population and sample details appear only when they are present in Evi's verified record.
Claim 01
Rosemary oil
Regrows hair as well as minoxidil.
- 01
Rosemary oil vs minoxidil 2% for the treatment of androgenetic alopecia: a randomized comparative trial
Skinmed · 2015 · PMID 25842469
Clinical trial
Both groups gained hair count at 6 months; rosemary caused less scalp itching.
- Authors:
- Not recorded
- PMID:
- 25842469
- Population:
- Not recorded
- Sample size:
- Not recorded
- Funding / conflicts:
- Not recorded
- 02
Can Plant Extracts Help Prevent Hair Loss or Promote Hair Growth? A Review Comparing Their Therapeutic Efficacies, Phytochemical Components, and Modulatory Targets
Molecules (Basel, Switzerland) · 2024 · DOI 10.3390/molecules29102288
Review
A review of plant extracts found that several have shown hair growth-promoting efficacy in clinical trials by modulating cellular pathways and growth factors.
- Authors:
- Not recorded
- PMID:
- — (PMC11124163)
- Population:
- Not recorded
- Sample size:
- Not recorded
- Funding / conflicts:
- Not recorded
Claim 02
Peppermint oil
Boosts follicle blood flow for faster growth.
- 01
Peppermint Oil Promotes Hair Growth without Toxic Signs
Toxicological research · 2014 · DOI 10.5487/TR.2014.30.4.297
Mice treated with 3% peppermint oil grew thicker hair than minoxidil controls. No human trial.
- Authors:
- Not recorded
- PMID:
- — (PMC4289931)
- Population:
- Not recorded
- Sample size:
- Not recorded
- Funding / conflicts:
- Not recorded
Claim 03
Castor oil
Thickens and lengthens hair.
- 01
Hair cosmetics: an overview
International journal of trichology · 2015 · DOI 10.4103/0974-7753.153450
Review
This overview article reviews the formulations and mode of action of various hair cosmetics, including shampoos, conditioners, and hair dyes.
- Authors:
- Not recorded
- PMID:
- — (PMC4387693)
- Population:
- Not recorded
- Sample size:
- Not recorded
- Funding / conflicts:
- Not recorded
- 02
Use of Castor Oil in Dermatology: A Narrative Review
Cureus · 2026 · DOI 10.7759/cureus.103289
Review
Reviews castor oil's skin and hair uses and the limited clinical evidence behind them.
- Authors:
- Not recorded
- PMID:
- — (PMC12978418)
- Population:
- Not recorded
- Sample size:
- Not recorded
- Funding / conflicts:
- Not recorded
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Alternatives / evidence compared
Compare your options
Matched on verified category, use, actives, formulation, claims, attributes, size, price and evidence. Relevance depends on the claim or use case—Evi does not name a universal winner.
View reportWhat is similar?
Also haircare / Comparable evidence-backed claim
What is different?
Different key active: Bis-aminopropyl diglycol dimaleate
Evidence for the relevant claim
For “Repairs broken disulfide bonds inside damaged hair.”: Limited — weaker evidence than the identified product’s closest claim.
What are you paying for?
No verified price is recorded.
View reportWhat is similar?
Comparable evidence-backed claim / Same promising claim-evidence level
What is different?
Different key active: Nano-hydroxyapatite, Xylitol
Evidence for the relevant claim
For “Remineralises enamel as well as fluoride, without fluoride.”: Promising — the same evidence level as the identified product’s closest claim.
What are you paying for?
No verified price is recorded.
03 / Northlight Lab
Overnight Retinal 0.1% Serum
Strong- Stronger evidence for “Smooths fine lines and clears breakouts faster than retinol.”
View reportWhat is similar?
Comparable evidence-backed claim
What is different?
Different key active: Retinaldehyde, Niacinamide
Evidence for the relevant claim
For “Smooths fine lines and clears breakouts faster than retinol.”: Strong — stronger evidence than the identified product’s closest claim.
What are you paying for?
No verified price is recorded.
04 / Lumen Form
LED Red Light Therapy Mask
Promising- Stronger evidence for “Boosts collagen and smooths wrinkles.”
View reportWhat is similar?
Comparable evidence-backed claim
What is different?
Different key active: 633nm red light, 415nm blue light
Evidence for the relevant claim
For “Boosts collagen and smooths wrinkles.”: Promising — stronger evidence than the identified product’s closest claim.
What are you paying for?
No verified price is recorded.
In The Evi Edit
Using it / 05
Practical context
A grounded starting point—not personalized medical advice.
Frequency
Follow the product label and introduce one new product at a time so you can notice benefits or irritation.
How to approach it
Check the active ingredients and concentration, then compare the product’s claim with the evidence rating above.
Cautions & costs
Patch-test topical products and check supplements against medications, allergies, pregnancy, and existing conditions.
Purchase notes / verified retailers
Where to buy
Prices, sizes and availability appear only when Evi has a current retailer record. Retailers are listed in Evi's fixed order, never by commission. Check final details with the retailer.
- SephoraPrice not verifiedSize not verifiedCheck retailerOpens retailer searchShop
- Ulta BeautyPrice not verifiedSize not verifiedCheck retailerOpens retailer searchShop
- AmazonPrice not verifiedSize not verifiedCheck retailerOpens retailer searchShop
- TargetPrice not verifiedSize not verifiedCheck retailerOpens retailer searchShop
- DermstorePrice not verifiedSize not verifiedCheck retailerOpens retailer searchShop
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