It's the most gifted bottle in every coily-hair bathroom, and the most misused. You buy it for the inches it promises, and three months later your roots feel heavy and your length hasn't moved.
That isn't castor oil's fault. Here are four things it genuinely does, one thing it doesn't, and the place we give it. Our step-by-step tutorial walks through the six steps of the Rituel Texture®, in order.
What carapate oil is
In the French Caribbean, nobody says castor oil. They say carapate oil, the Antillean name for it, and for a long time it was made at home from seeds that were pressed and then heated. Same plant, same oil, but with a household history that the shop-bought bottle has lost along the way.
What makes it unusual comes down to a single component. Castor oil is almost 90% ricinoleic acid, a fatty acid found practically nowhere else at that concentration, and it's what gives the oil its very high viscosity and its coating power (Patel et al., Lipid Insights, 2016). In practice: a heavy molecule that stays on the surface, coats well and penetrates poorly.
The mistake I correct most often is the belief that oil moisturises. At my grandmother's, carapate oil was added to the hibiscus infusion we made together, never used instead of it. And when it was time to do our hair, a little carapate with cocoa butter, on the ends. The oil went with the care. It never replaced it.
Ghana Elin, founderBenefit 1It adds slip and makes styling easier
This is its first strength, and the most underrated. A coily section coated in a thick oil slides more easily through your fingers, separates without snagging, and stands up better to the handling of a long styling session. The women of our grandmothers' generation knew what they were doing when they kept a bottle within reach on braiding day.
Watch out, though, for the shortcut that usually follows: because it adds slip, people assume it's made for detangling. In the Rituel Texture®, detangling starts with the fingers on dry hair, with no product required, then moves on to the Peigne de Man Dol' on hair coated in mask. Dry hair isn't what breaks. A comb dragged through dry, bare hair is.
Benefit 2It coats the hair and limits mechanical breakage
A film of oil on the cuticle reduces friction between strands and cushions the everyday rubbing: your pillow, your coat collar, your scarf in winter. On ends that are already a few years old, that's no small thing.
But we should be clear about what this film isn't. Oils don't all behave the same way with the hair fibre: the landmark study on protein loss in hair compared coconut oil, mineral oil and sunflower oil, and only coconut oil, with its small, linear molecule, reduced that loss, while the other two stayed on the surface (Rele and Mohile, Journal of Cosmetic Science, 2003). Castor oil wasn't tested in that study, and its much heavier molecule gives no reason to expect better. It protects from the outside. It doesn't repair, and it doesn't replace Le Masque Réparateur.
Benefit 3It soothes a tight, uncomfortable scalp
On dry skin that feels tight the day after a wash, a few drops worked in with your fingertips bring instant comfort. It's an occasional, sensible use, as long as you measure by the drop and not by the spoonful.
Two caveats, and both matter. First: on an oily or flaky scalp, oil does the exact opposite, because it feeds the yeast involved in flaking. That's the one case where we firmly advise against it, and our guide to dandruff explains how to tell dry skin from an unbalanced scalp. Second: if itching, patches or flaking persist despite a suitable routine, that's a job for a doctor or a dermatologist, not for an oil.
Benefit 4It gives the ends a glossy finish
One drop warmed between your palms and pressed onto the ends visually smooths the cuticle and rescues that dull, end-of-the-week look. It's a finishing touch, not a treatment, and it belongs between two routines rather than in the routine itself.
On its own, its thick texture is hard to work with. Mixing it with a lighter oil makes it manageable, and our notes on three light oils and what they really do tell you which to choose for the result you want. For an overview of oils and butters and the only two moments they're useful, see the best oils for coily hair.
What it doesn't do
It doesn't make hair grow. No oil applied to the skin changes the speed at which the follicle produces hair, and we know of no serious study showing that castor oil does. The length you gain is gained further down the line, by breaking less: that's retention, a different subject altogether, covered in our eight tips for length retention.
Nor does it lock in moisture, in the usual sense of the phrase. For a long time we wrote here that you should moisturise, then seal with oil, and we no longer say that. Locking in moisture is step 06 of the Rituel Texture®, and it's done with La Crème Coiffante, which helps hold on to the moisture brought by the wash, applied generously before a protective braid or twist. A drop of light oil can top it up on the ends between two routines, and that's all.
The most common mistakes
- Applying it to dry hair hoping to moisturise: it locks in the dryness instead of the water.
- Being heavy-handed: the fibre gets weighed down, the roots get clogged, and the next wash turns into a stripping session.
- Leaving it on overnight under a cap, every week, as a deep treatment.
- Trying it without a patch test: any new oil goes on a small area first.
Its place in the Rituel Texture®
Let's settle the oil bath question first, since it comes up in every conversation about castor oil. It's an occasional treatment, once or twice a year at most, and we explain in the article devoted to it why repeating it every week saturates the fibre instead of nourishing it. To prepare for a wash, Chadian finger detangling on dry hair is enough, and works far better: see also what becomes of the pre-poo in our method.
That leaves carapate oil with a clear, modest role. Between two routines, a drop on the ends in the evening when they look dull or dry. Now and then, a few drops on a tight scalp, as long as it's neither oily nor flaky. And when styling, mixed with a lighter oil, to give slip to a section you're about to braid for a long time. Everything else is the job of the full routine, every seven to ten days.
Is such a rich oil right for your hair?
Our experts go through your routine with you online and tell you what, in your case, calls for oil and what calls for something else.
Book a consultationFrequently asked questions
Does castor oil make coily hair grow?
Jamaican black castor oil or cold-pressed castor oil?
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Sources
- Patel V. R., Dumancas G. G., Kasi Viswanath L. C., Maples R., Subong B. J. J., "Castor Oil: Properties, Uses, and Optimization of Processing Parameters in Commercial Production", Lipid Insights, vol. 9, 2016.
- Rele A. S., Mohile R. B., "Effect of mineral oil, sunflower oil, and coconut oil on prevention of hair damage", Journal of Cosmetic Science, vol. 54, no. 2, 2003.
