Castor oil: it’s the all-natural remedy that’s received glowing testimonials across the web for its hair growth potential - but is it really the secret to a fuller lash and hair line? We found out

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There are certain all-natural remedies that have stood the test of time - coconut oil , apple cider vinegar , reads like a shopping list at Whole Foods. However, there’s one that a growing number of people swear by for meeting their hair care needs - castor oil, the golden (or dark brown) elixir that, if the glowing testimonials on blogs and Reddit are to be believed, holds the key to a fuller head of hair and a thicker lash line too.

Castor oil benefits for hair

There are two types best known for their root-boosting benefits - castor oil which is golden in colour and black castor oil, which is made from roasted castor seeds and is said to be more clarifying due to its more alkaline make-up. Both are quite heavy in feel and texture which can be a little off-putting, but they make up for that with their impressive vitamin E and fatty acid content. “Castor oil is rich in ricinoleic acid which has anti-inflammatory, anti-fungal and anti-bacterial properties,” Guy Parsons, certified trichologist and founder of My Hair Doctor tells me - the perfect scalp-calming combo.

Castor oil for eyebrows and eyelashes

The ricinoleic acid content can also keep brows and lashes healthy too. “It’s great for combating damaged lashes and keeping them moisturised and conditioned,” says Jaimineey Patel, Head of Training at Blink Brow Bar . It’s especially handy if treatments such as tints and lash extensions  have left them dry and split.

Can castor oil actually make your hair grow?

Another key benefit of castor oil is its ability to increase blood flow around the scalp, which is why many people believe that it can increase hair growth. There needs to be more evidence though, says Guy, to show a direct connection: “There is no link between follicular hair growth and castor oil, and any suggestion otherwise is anecdotal.” Considering how complex the reasons for hair loss  and thinning hair can be, this makes perfect sense.

That’s not to say though that castor oil isn’t worth incorporating into your regime. If used properly, it can improve the condition and flexibility of your strands, to prevent them from snapping off due to dryness. “Being an oil, it will have clear moisture and replenishment benefits for thicker, coarser hair that requires more moisture than other hair types,” says Guy.

Its viscosity actually works in its favour in these cases notes Gemma Hume, Afro Specialist at Paul Edmonds London . “Castor oil is naturally thicker in consistency so it’s great for coating curly and Afro hair and sinking right down to the roots,” she tells me. “Always apply it to the scalp, massaging it in, and leave it on the hair with a plastic cap, under heat, for 30 minutes to intensify the penetration of the oil.”

How much castor oil use

As mentioned earlier, castor oil’s much richer than other oils and, unless you have Afro, thick or curly hair, using it neat can actually end up being counterproductive. “Use it in a diluted form, as it may be very difficult to remove and any benefit from the oil will be undone by the six times you need to wash your hair to get it out!” cautions Guy. Good point.

If you’re using it as a scalp or moisture treatment, he recommends diluting it so that it’s one part castor oil, five parts almond or argan oil (which are both lighter). Apply sparsely to start with - if you have hair that gets greasy quickly, just apply it to mid-lengths and ends (hair’s more damaged towards the ends anyway) and avoid using it in conjunction with other moisturising products to prevent a case of ‘over-hydration’ . If greasiness fears are still weighing on your mind, look for it as a core ingredient in your hair care products instead (such as those in our edit below). If it's a serum or conditioner castor oil should be among the top ingredients listed in the ingredients list to be a worthwhile amount. For shampoos it will be lower done, maybe line three or four, as shampoos still need to be clarifying.

The same approach applies to its use on eyebrows and eyelashes too. While castor oil won’t necessarily help them grow quicker, incorporating products that have the ingredient in them into your nightly regime can certainly go some way in making them stronger and less prone to breakage. “It’s best when combined with other ingredients,” says Jaimineey. “For example, our BBB London Luscious Lash Oil contains seven essential oils, all of which work in harmony to grow, stimulate and hydrate lashes.”

You could use castor oil neat, but it won’t feel all that comfortable and you might run the risk of causing irritation if you do happen to overdo it on the application.

The bottom line

Castor oil won’t boost your hair’s growth from the follicle, but it can improve the condition of your hair so that it doesn’t break off before reaching a certain length. It can help boost scalp health by increasing circulation, but due to its stickiness, the majority of hair types could benefit from using it in a product that combines it with other ingredients, rather than using it neat.

From straight up to mixers, here are nine castor oil cocktails that leave hair softer, stronger and shinier.

Centred En Root Scalp Treatment, £36 for 100ml

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Vegan, natural and cruelty-free haircare brand Centred was set up after founder Laura Tudor's hair began to fall out as a result of stress from her fast-paced career. She wanted a brand to care for her hair as well as stimulate growth in the future. This scalp treatment, complete with easy to use nozzle, has a calming scent of lavender and transforms to cream when mixed with water. Along with castor oil, it also has salicylic acid to rid your roots of product and dead-skin build-up and stimulate blood flow and soothe irritation. Other ingredients include peppermint, rosemary and hemp seed for an all-star lineup.

Centred also have the Calma Conditioner , £22 for 250ml, in the collection which as well as castor oil, includes squalene to hydrate and camellia japonica oil, which prevents moisture loss.

Monpure Hydrate and Soothe Scalp Serum, £96 for 50ml

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This slightly medical smelling serum (smells very faintly of TCP) has castor oil high in the ingredients list, along with a cocktail of ingredients including pro-vitamin B5 to lock in moisture and allantoin known for its healing properties. 100 people trialled this over four weeks with 85 per cent of people agreeing it had a positive effect on the health and condition of their scalp.

My Hair Doctor Volume-ise Hair Food Growth Booster, £22 for 120ml

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This supercharged spray containing castor oil, niacinamide and creatine helps fortify strands from root to tip.

Superdrug Black Castor & Shea Hydrate & Replenish Conditioner, £5.49 for 400ml

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This award-winner is particularly great for brittle hair types in need of a hydration upgrade.

Bleach London Power Deep Treatment Shot, £6.50 for 20ml

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This syringe injects some much-needed moisture into overprocessed hair with the help of wheatgerm, oat lipids, baobab, vegan protein and of course, castor oil.

BBB London Luscious Lash Oil, £24 for 7.5ml

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If lash extensions have left your flutter flailing, this nourishing overnight treatment can help get it back to its best.

MORE GLOSS: Your post-eyelash extension rehab plan

Grow Gorgeous Scalp Detox, £21 for 190ml

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Castor oil beads along with white willow bark extract and pomegranate fruit enzymes help slough off dead skin cells and product build-up, to clear the way for healthier hair growth.

Shea Moisture Jamaican Black Castor Oil Strengthen and Restore Shampoo, £10.99 for 506ml

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This sulphate-free shampoo  enriched with Jamaican Black Castor Oil and organic shea butter provides a more caring cleanse for chemically processed and breakage-prone hair.

Pukka Castor Oil, £9.99 for 250ml

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If you’re looking for the pure thing, try this. Definitely one for those with especially thick and parched hair.

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