Olive oil for the hair: likely benefits – and some cautions

The healthful components appear ideal for haircare, but ‘care’ is the watchword

In an article published at the end of last year on the US-based website Insider.com, remarkable for both its thoroughness and its caution about unproven claims, writer Erin Heger outlined the multiple perceived and probable benefits of olive oil in haircare.

The article – carefully reviewed by board-certified dermatologist Dr Debra Jaliman – focused on olive oil’s rich content of moisturising ingredients like squalene and oleic and stearic acids.

“The science so far is limited,” Heger wrote, yet there is “plenty of anecdotal evidence to support olive oil’s beauty benefits for hair”.

“The belief that olive oil is good for hair comes from its components, particularly oleic and stearic acids. These fatty acids not only offer health benefits when consumed, but may also offer cosmetic benefits to your hair when applied topically.”

Oleic acid is an emollient with softening and moisturising properties. (An emollient covers the skin with a protective barrier to help seal in moisture.) Olive oil’s high oleic acid content is thought to penetrate the hair shaft to restore moisture, Heger quoted Fabio Scalia as saying, a certified cosmetologist who owns a string of salons under his name.

Squalane is another type of emollient popular in skincare products due to its ability to hydrate skin.

In terms of moisturising, “the chemical makeup of olive oil shows potential for a moisturising effect when applied to the hair or skin”.

When it comes to helping prevent split ends, those same moisturising properties “may also help strengthen the hair and increase its elasticity, helping to prevent breakage or split ends”. Scalia cautioned, though, that olive oil cannot repair split ends once they occur.

“While olive oil can help soften the hair and keep it healthy, the best way to deal with split ends is to get regular haircuts to remove any breakage,” the article stated.

Many people claim olive oil makes hair grow faster, but the data on this is limited, according to Patrick Zito of the University of Miami Miller School of Medicine.

Heger wrote: “A 2015 study found that a component in olive oil known as oleuropein does have an impact on the hair-growth cycle in mice, but similar studies have yet to be conducted in humans.”

And, quoting Karan Lal of the Society of Paediatric Dermatology, “Many individual factors, like diet, genetics and hormones, can impact hair growth, making it hard to study olive oil’s direct effects on hair growth in humans.”

Still, olive oil does contain vitamin E, which can help smooth hair and reduce frizz, giving the appearance of hair growth, Scalia pointed out. “Vitamin E’s antioxidant effects may also support a healthy scalp, which could promote hair growth, but more research is needed,” Heger added.

Regarding possible risks of using olive oil in the hair, she cited Lal, who warned it “can also be a risky choice depending on your hair type”.

Scalia recommended olive oil “for people with curly, thick and coarse hair that is more prone to frizz and dryness. Olive oil applied to fine or straight hair, on the other hand, could potentially weigh it down and make it feel greasy.”

You also should not use olive oil in your hair if you have dandruff, Zito said. That’s because olive oil promotes the growth of the yeast that causes dandruff.

Olive oil “can actually worsen the condition like throwing kerosine onto a fire”, he highlighted. “The more often you apply it, the greater the chance of exacerbating the condition.”

Heger then addressed the claim that olive oil can protect the hair against damage from heated hairstyling tools, but Zito noted that extra virgin olive oil has a smoking point of 320°F (160°C), while many flatirons, wands and curling irons reach temperatures much higher than that.

“At [320°], the oil begins to smoke, produce fumes and create free radicals” that can damage hair, Zito said.

Lal recommended applying cold-pressed extra virgin olive oil to the ends of the hair, not the scalp. The exact amount of olive oil required will vary from person to person, Scalia added, but it doesn’t take much – just enough to work it through the middle of your hair down to the ends.

Olive oil can also be difficult to wash out, so Scalia advised using it prior to shampooing as a moisturising treatment. Leave it on for about 15 minutes and then wash it out with a clarifying shampoo and a replenishing conditioner. Lal recommended doing this once or twice a week.