Best Natural Oils That Penetrate The Hair Shaft (And Why It Matters)

Not all natural oils work the same way. Most oils simply sit on or coat the hair strands. Some are able to penetrate the hair shaft instead of simply coating the outside of the hair.

These penetrating oils are good to use on relaxed hair because they can help reduce moisture loss, minimize hygral fatigue, and improve the overall condition of your hair when used as part of a healthy wash day routine.

Let’s talk about those oils and compare the pros and cons of each.

(This post includes affiliate links. Should you click an affiliate link and make a purchase, I may receive a small commission.)

What are penetrating natural oils?

These are plant-based oils that are able to be absorbed deep into the hair shaft versus sitting on the hair like other oils. The reason is the makeup of the oil. 

This is going to get a little technical, so hold on. These oils have what’s called a small molecular structure or low-weight fatty acid. This makes it easier for them to penetrate hair strands better than other oils.

The three main oils that fit this category are avocado oil, coconut oil, olive oil, and argan oil.

Benefits of penetrating natural oils

There's a reason these are some of my favorite natural oils to use. That's because penetrating oils help with improving hair elasticity and flexibility by nourishing, strengthening, and moisturizing within the hair strand.

Penetrating oils also have water-repelling capabilities. They penetrate the hair shaft when applied to dry hair. This prevents the hair strands from soaking up lots of water, which can lead to what is called hygral fatigue.

Related read: Natural Oils That You Can Use On Your Relaxed Hair

How penetrating oils help reduce hygral fatigue

Hygral fatigue is the name for hair damage caused by water expanding and contracting the hair strand. Excessive amounts of water cause the hair strand to expand and contract when it enters and leaves the hair strand. The damage caused is a weakened hair strand that may break and has porosity issues.

By using penetrating natural oils, you can help to prevent or lessen the amount of hygral fatigue damage to your hair. This is because they get into the hair strands, basically soaking the hair. This creates a barrier for water, keeping water from swelling up the hair shaft. Less swelling means less hair damage and breakage.

Types of penetrating natural oils

As previously noted, there are four oils designated as penetrating: avocado oil, coconut oil, olive oil, and argan oil. Here's more on each, including the benefits and tips for using them on relaxed hair.

Argan oil

Best for

• Use on all hair types because of its lightweight texture
• Dry or damaged hair
• Managing frizz and flyaways

Pros

• Seals the hair’s cuticles, locking in moisture
• Can be used on wet and dry hair
• Helps protect from heat and environmental damage
• Can be used on the hair and scalp

Cons

• Not good for those with a nut allergy
• Overuse can cause greasy hair

How I use it

I’ve never used this on its own. I’ve always used argan oil as part of a serum that includes other oils. That being said, argan oil can be used 

• to detangle the hair
• as an overnight pre-shampoo treatment 

Avocado oil

Best for

• Taming frizzy hair
• Prevention of split ends
• Moisture retention
• Nourishing

Pros

• Can be used to hydrate skin, including the scalp
• Can be used on relaxed hair

Cons

• Can be a little thick and weigh down fine hair

How I’ve used it

• Detangling because it helps to add slip
• Sealing in moisture after moisturizing
• Adding shine

More about avocado oil.

Coconut Oil

Best for

• Reducing protein loss
• Hair treatments
• Damaged hair
• High porosity hair

Pros

• Helps with moisture retention
• Helps with protein restoration

Cons

• Will solidify at a certain temperature. Not just in the jar, but also on your hair. So this oil is better suited for warmer temperatures
• Can weigh down fine hair
• Tends to sit on low porosity hair because of the moisture absorption resistance this type of hair has

How I use it

• In hot oil treatments
• As a sealing oil
• As a pre-shampoo treatment

More about coconut oil.

Olive oil

Best for

• Dry and damaged hair
• Hair prone to frizz

Pros

• Locks in moisture
• Smooths frizz
• Soothes scalp
• Adds shine
• Increases hair manageability

Cons

• It’s a heavy oil that can weigh down fine hair strands
• Too much can cause a greasy feeling 

How I use it

• How oil treatments
• Pre-pooing
• Adding it to my hair conditioner as an enhancer

More about olive oil.

Shop these oils