Olive oil has been hailed as a hair-healing treatment for ages. And today, you'll read about its wonders all over the internet. It makes sense as to why: a hair care cure for dryness and damage, found right in your kitchen? Plus, it contains many of the good-for-you ingredients that you find in commercial products? Especially those looking for easy, natural, DIY options, the appeal is undeniable.

In order for your hair to remain healthy, it needs to retain moisture and nutrients, and those are often depleted with hot tools, chemical processing, surfactants in shampoos, and daily wear and tear. It also needs protection from environmental stressors, like sun and pollution, as they cause free-radical damage. When your hair is damaged, it can become more porous, meaning it loses water much faster.

Olive oil plays a role in helping hydrate hair but not in the way you might think: Olive oil is a monounsaturated fat. Hair actually has the ability to absorb monounsaturated fats, according to research1. (According to one study21, they've been able to document the absorption of certain oils by tracking the thinning film that surrounds the strand, and it also shows that doesn't happen with all oils, like mineral for example, so while some smaller oil molecules can penetrate hair, some will only sit on top.)

Research suggests4, olive oil can also act as a lubricant for strands to reduce breakage. Shockingly, a significant amount of damage to hair can actually happen during the shower: Hair is weakest when wet, then when you add in surfactants from shampoo and the scrubbing motion, you cause friction between strands. This friction can lead to raised cuticles, stretching, and splintering. When you apply an oil before washing, the film helps minimize the chances of this.

It should be noted that these benefits only come when choosing the right type: Opt for extra-virgin organic olive oil, which is the least processed and contains more of the hair-helping nutrients explained above.

As with all good things in life, it's not right for everything or every woe.

There are many claims that it can help with dandruff by moisturizing flaky, scaly patches—as well as being antimicrobial. However, most dermatologists refute this.

According to board-certified dermatologist Whitney Bowe, M.D., "Dandruff is caused by a yeast on our scalp, and if you use olive oil, you are feeding that yeast, which might make dandruff worse." (She also notes she's not against using olive oil as a hydrator, especially on the ends, but it might not be right for everyone.)

Another potential side effect: If you are acne-prone on your chest or back, and your hair is long enough to touch the area, you might be unintentionally clogging pores and leading to worse breakouts.

Those with extremely dry hair or those with kinky and curly textures will benefit the most from olive oil, notes Corney, who says it is one of her favorite oils for her clients. This hair texture is naturally more porous and, therefore, loses moisture faster. Also because of the winding strand pattern, it has more points on the hair that are prone to breakage (your hair is more susceptible to damage at curves and turns), so it needs more lubricating, especially during the detangling or washing process.

However, it's too heavy of an oil for those with fine or straight hair. It will weigh down strands and make the style appear greasy, especially when applied at the roots. These hair types would benefit more from a thinner option with less slip, like jojoba or argan oil.

Using olive oil isn't just as simple as pulling it off your kitchen counter and dosing your strands with it. It can be, but there are a few more effective ways to use it, depending on your needs.

As a pre-shampoo treatment: As noted above, washing your hair can actually cause damage to the strands through friction and surfactants. So before you take a shower, evenly apply oil—the amount will depend on length and thickness. If you are especially dry, we recommend coating the whole strand. Or if you are prone to oily scalps, you can just focus on mid-shaft to the ends.

For tending to your ends: While nothing can fix dry and split ends besides a trim, you can temporarily improve the look of them. It's as easy as applying a tiny bit to the bottom of the hair: The oil adds shine to the area, making it appear less damaged (dullness is a key sign of dead ends). And, while this particular study didn't test olive oil specifically, it showed that regular use of oils in general may help prevent future split ends by protecting it from physical damage.