Exactly why your hair is always oily and how to fix it, according to a hair expert.

We're going to take a wild guess. 

If you're reading this right now, we're going to assume that you have oily hair. You wash your hair more often than you'd like to and you reach for dry shampoo (we assume you have a favourite) almost daily. Are we right?

Don't worry, us too.

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Being blessed with oily hair comes with very few pros. One being, you can slick your hair back without putting product in it. Woop! But most of the time, it's quite an annoying trait to have.

Carolyn Evans-Frost is a trichologist at Absolique Hair Health Clinic in Brisbane, and she knows more than a thing or two about oily hair, including what causes it and how to fix it.

So read on for her advice and guidance, plus, some handy tips for oily hair.

So what actually causes oily hair?

Before we get into exactly how to help our oily hair, it's good to know what causes it. As Carolyn explains, there are three main reasons that hair produces oil.

"Every hair on our head has its own oil gland," Carolyn said. "Oily hair is the result of an overactive oil gland, hair thinning where the hair has reduced in size (diameter) but the oil gland remains the same size, or Essential Fatty Acid (EFA) deficiency – when levels are low in the body and the body tries to let you know by producing more oil.

"Excess oil generally means a deficiency of sort, to do with EFA’s or fat-soluble vitamins. Low Vitamin D is another cause, as are hormone imbalances," she said.

So, while some tips and products might help in the short term, there might be a deeper problem causing the oil, that needs addressing. 

Ok, now what is the best shampoo and conditioner for oily hair?

Anyone with oily hair knows the frustration of having to wash your hair far too often. You'll have one good day where your hair is clean and fresh, but by the next day, it's a greaseball and it's time to wash it again. 

Now, you might wonder whether there's a certain shampoo and conditioner you should use to help with the oil. But as Carolyn explains, there's actually a product you should use before them that will help massively.

"It's the oily scalp that results in the oily hair, so I would recommend a suitable scalp cleanser to actually cleans the oil off the scalp and clean the oil glands first," she explained.

By using a scalp cleanser pre-shampoo and conditioner, you're removing the daily buildup of oil, dirt and bacteria before cleaning your hair. Think of it like taking your makeup off before washing your face! Same thing.

After you've used the scalp cleanser, you can go in with your favourite shampoo or conditioner for your hair type (thin, thick, coloured, damaged, etc) because it'll no longer be oily. But remember: don't apply either to your scalp (to avoid more oil).

"This is a different concept to what we are taught, but is the best thing to overcome that oily scalp and oily hair. It can be life-changing," Carolyn said.

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Are there any products or ingredients us oily-haired folk should avoid?

While there are plenty of products you can use, there are some you should avoid.

"As I mentioned earlier, keep shampoo and conditioner off the scalp and avoid stripping products (like anti-dandruff products)," Carolyn said. "We want to clean the scalp safely not strip it, which can cause all sorts of other problems." 

"I would also avoid the coating type of products like the synthetic silicones as this can trap the oil onto the hair leaving it lank and weighed down," she added.

Products with synthetic silicones seem great because they leave the hair feeling soft and shiny, but they're generally doing more harm than good. So stick to products that fix the problem (like a scalp cleanser and good quality shampoo and conditioner), rather than products that just mask it.

The best tips to combat oily hair.

Some days, you can't fix oily looking hair. You'll be running out the door, desperately wanting to have your hair out and need a solution, stat. 

Here are some things you can do beforehand that will help:

• Use a scalp scrub before you wash your hair, as Carolyn recommends.
• Applying dry shampoo before you go to bed. Once you wake up, zhoosh your hair and add a little more dry shampoo, if needed.
• Sleep on a silk pillowcase (it helps reduce sweat and oil).
• Apply dry shampoo when needed (ugh, it does actually work so may as well use it). 

But always remember, despite using these handy tips to mask the oil, there's generally a deeper problem causing the production of oil.

"Problems with hair and the scalp are a sign something is not right within, don’t ignore the signs," Carolyn said. "If the hair is increasingly getting oilier, there is a problem with the scalp, hair, health or a combination."

Feature image: Getty.