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Botanicals for hair & scalp

Hair

Oils for growth, shine and breakage, and which of them have data behind them. Covers scalp, brows, lashes and beards too.

8 articles · 7 botanicals

Flat illustration of a smiling bearded man pouring castor oil on his head, surrounded by castor plants with red spiky seed pods
Illustration

Evidence Check · Castor oil

Castor oil and your hairline: what the evidence actually says

Journal Botanica Editors · Last reviewed November 3, 2026 · 13 sources

Castor oil (from Ricinus communis) is a venerable hair tonic in many cultures and has attracted recent scientific attention. Narrative and systematic reviews of castor oil in dermatology summarize two recurring points: laboratory and computational studies suggest mechanisms worth testing, and human clinical evidence that topical castor oil grows new terminal scalp hair is weak or absent in the literature cited here. These reviews also emphasize castor oil’s established role as a heavy conditioning oil rather than a validated hair-regrowth therapy. [1, 2, 3]

Below I separate what the lab work suggests, what small animal and human studies actually measured, and what we can reasonably tell people who care about a receding hairline. Continue reading

Botanicals for hair

Full Index →
  • Castor

    Ricinus communis

    Thick, sticky, mostly ricinoleic; nicer conditioner than grower

  • Argan

    Argania spinosa

    Morocco’s liquid gold for soft skin and shinier strands

  • Coconut

    Cocos nucifera

    Lauric‑rich oil that actually gets into hair

  • Jojoba

    Simmondsia chinensis

    Desert liquid wax that softens skin and tames hair

  • Pumpkin seed

    Cucurbita pepo

    Seed oil with hair hopes, allergy cautions, and small trials

  • Rosemary

    Salvia rosmarinus

    Evergreen kitchen herb with a head for haircare

  • Marula

    Sclerocarya birrea

    Silky, oleic‑rich oil from the marula kernel

Everything on hair

  1. Research Desk

    • Hair

    Pumpkin seed

    Pumpkin seed oil and thinning hair

    One randomized, placebo‑controlled trial found men taking oral pumpkin seed oil capsules had a meaningful hair‑count gain; animal studies and small topical trials add plausible mechanisms but do not settle whether rubbing oil on your scalp will help. Evidence is suggestive but thin and largely unreplicated.

    3 min read

  2. Evidence Check

    • Hair

    Coconut

    Coconut oil and hair breakage: one of the few oils with real data

    Coconut oil is one of the few hair oils shown in lab work to penetrate the hair shaft and to reduce protein loss during washing. The support comes mainly from in‑vitro and small human observational work; large controlled clinical trials are still lacking.

    4 min read

  3. Origins

    • Hair

    Scalp

    Scalp oiling: tradition, trend and what the science says

    Scalp oiling is an old care ritual whose modern popularity rests on texture, comfort and smell as much as any biological effect. Laboratory work shows coconut oil can change hair-fibre mechanics and has antibacterial activity in vitro; a randomized trial in preterm infants shows topical coconut oil increases skin moisture. Clinical evidence for scalp oiling specifically is thin.

    4 min read

  4. Index Explainer

    • Hair

    Beard

    Beard oils: what’s actually in them and what they do

    Beard oils are mostly light carrier oils (jojoba, argan, sometimes castor) plus fragrance; as topical emollients they soften coarse facial hair and can reduce skin inflammation and itch, but there’s little direct human evidence that they make beards thicker or grow faster. (Evidence for moisturising and anti-inflammatory effects comes mainly from lab, animal and formulation studies.)

    4 min read

  5. Myth Busting

    • Hair

    Argan

    Argan oil for frizz: shine, not repair

    Argan oil’s value for frizz is primarily cosmetic: its fatty acids and surface‑active lipids coat the hair, smooth the cuticle and add shine. The literature here shows compositional differences, processing effects, and antioxidant activity — useful context for styling — but not clinical proof that oil restores broken ends or structurally repairs hair.

    4 min read

  6. Evidence Check

    • Hair

    Castor oil

    Castor oil for brows and lashes: does it thicken anything?

    The castor-oil-for-lashes story is mostly anecdote and small preclinical work; systematic reviews find no strong human evidence for hair growth, while product formulations sometimes hide stronger, drug-like ingredients that do have effects and safety concerns.

    5 min read

  7. Index Explainer

    • Skin
    • Hair

    Jojoba

    Jojoba isn’t an oil, and why that matters for your skin

    Jojoba is chemically a liquid wax made largely of wax esters, the same lipid class that contributes substantially to human sebum. That chemical kinship and jojoba’s compositional stability explain many of its practical advantages, but controlled human trials showing it ‘balances’ oil production are lacking.

    5 min read