Can Castor Oil Really Thicken Hair?

Curated by Claudia Shannon / Research Scientist / ishonest

I mix a few drops with olive oil to make a sleek makeup remover. Takes everything off quickly and leaves my skin super smooth.

Sometimes, I use the mixture on my hair, too. It makes it silky soft and super shiny.

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Lately, I’ve heard rumours it can thicken hair, too. But I’m afraid this is a feat it can’t pull off…

Can Castor Oil Thicken Hair?

Here’s the thing: hair thickness is determined by genetics. That’s why it’s so difficult to increase it.

I’ve scoured scientific journal after scientific journal and could find NO evidence that castor oil thickens hair. None. Nada. Niente.

Sorry, ladies! When it comes to hair thickness, you’re still stuck with what you were born with.

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How Did This Myth Originate?

There’s a little kernel of truth in every myth, isn’t there?

Castor oil can’t make your hair grow thicker. But it can fool you into believing it made your hair grow thicker. Huh?

Castor oil is sort of like a glue. It’s thick. Once you apply it, it stays put. This alone can make your hair look thicker. Add the small particles of dust the oil attracts and your locks look even thicker.

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But… there could be another reason. A lot of people mistake hair thickness for hair density. Hair density is the number of hairs in an area of the scalp.

Castor oil has anti-inflammatory and anti-bacterial properties that can treat follicles infested with bacteria. Once that’s treated, more hair will grow in that area.

One more thing. You usually massage castor oil into your scalp. Massage can stimulate blood circulation, bringing nutrients to your hair faster. It’s another trick that helps your hair grow back faster. Bu you don’t need castor oil for this. The massage alone can do it.

The Bottom Line

Hair thickness is determined by genetics. Castor oil won’t affect it. It’ll just give you the illusion of thicker hair.

Read more on: hair, castor oil


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