How often should you really be washing your hair? We asked an actual expert.

Fact: There's no beauty topic that'll divide a group of close friends quite like hair washing schedules. We're all curious to know what other people do with their hair - because it seems like everyone has a different thing going on. Some people are all about that squeaky-clean feeling and wash their hair on the daily, while others prefer to stretch out their routine to a couple of times a week and use dry shampoo to fool everyone (genius). 

It's a complicated game.

Listen to Mamamia's podcast for your face, You Beauty, where we speak with celebrity hairstylist and salon owner Renya Xydis about how to get salon smooth hair at home. Post continues below. 

But how often should we really wash our hair? To save you having another heated debate over brunch, we've done you guys a solid and hit up a trichologist to answer the most common questions about washing your hair. Never heard of a trichologist? They may sound like a type of dinosaur, but trichologists are actually dermatologists who have an expertise in hair and scalp health. They talk about this kind of stuff with their clients every single day, which proves just how important it is.

Alrighty, let's go!

How often should we be washing our hair?

"There is no real right or wrong answer," said trichologist Carolyn Evans-Frost at Absolique Hair Health Clinic in Brisbane, who notes that it will depend on the individual and the scalp condition.

To give you a bit of a guide, here's how often you should wash your hair according to your scalp type:

If you have an oily scalp: "If someone has a naturally oily scalp, they may need to wash daily for hair styling reasons," said Evans-Frost. 

"I have found with many people now working from home, hair washing and hair styling has reduced simply because they do not need to look a certain way for work every day. Their scalp is still healthy." 

If anything, pushing out your washing routine to every second day or every third day will help encourage your scalp’s natural oil production to normalise.

If you have a dry scalp: If you have a dry scalp and you're washing your hair every day, you're going to have a bad time. A dry scalp can lead to super dehydrated strands (hey, breakage) because there's not enough oil being produced. On top of this, the effects of cooler weather and a lack of vitamin D can lead to "increased scalp scale" (which is actually different to dandruff). 

"During this time we may need to use a more prescriptive scalp cleanser every other day to get things back to normal, then we reduce back to three washes a week and where suitable, twice a week." This will give those natural oils a chance to rebalance your scalp - so try your best to stretch it out a little.

If you have a normal scalp: Look at you with your normal scalp, you lucky thing! "For the sake of a normal healthy scalp, washing twice a week is sufficient - once a week tends to lead to scalp conditions," said Evans-Frost. 

"It's important to remember that the scalp is skin and is constantly dying and dividing, just like the rest of our skin. So dead skin cells tend to build up if not removed by washing." Got it.

Is it bad to wash your hair every day?

While there are a whole heap of different opinions on this topic (just ask Google - he's had enough), generally it just depends on the scalp condition and what is being used. 

"A dry scalp using harsh products and ingredients will become worse if washed this way every day," said Evans-Frost. "However, someone with a scalp condition needing treatment, or the oily scalp mentioned earlier, can benefit from washing daily with the right products."

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"Hair type and condition need to be considered here, too. Dry, damaged hair can have a negative reaction from over-washing and styling, however fine hair can 'look' better from daily hair washing and styling." 

Our advice? Listen to your scalp and hair. They can tell you some wonderful things. Also, both very fun at parties.

So, what happens if you don't wash your hair enough?

We're all up for minimal effort on the beauty front, but if you're stretching out your hair washing sessions with dry shampoo on the reg, just be careful - because that stuff builds up. And you'll know when you've reached the you're-really-bloody-pushing-it stage of dirty hair. 

Evans-Frost said, "Scalp oil can build up in the hair follicle causing a blockage, this can then turn into a painful scalp pimple if inflammation or bacteria get involved. This can result in a scalp sore which can then lead to scalp bleeding which is not ideal." Eek! A pimply, infected scalp is definitely not worth skipping a post-workout wash, hey. Like, at all. 

"Dead scalp skin can also build up and get trapped in the oil forming larger scales and sometime even plaques. This is not healthy for the scalp and can turn into scalp conditions such as seborrheic dermatitis or pityriasis amiantacea - to mention a few commonly seen in my clinic," revealed Evans-Frost. 

"A big complaint is also itchy scalp. An unhealthy scalp is more likely to be itchy creating scratching habits which can damage scalp and hair."

So, yeah. None of this is great. As a general rule of thumb, make sure you're getting in at least one wash a week, people.

What's the best way to fix a messed-up scalp?

"I recommend using a scalp cleanser and doing a rinse and repeat until you form a cleansing foam (always at least twice!). This will also cleanse the hair as the product will run through the hair when being rinsed out," said Evans-Frost. 

"For hair longer that 10cm, you would then use a hair shampoo and conditioner, keeping it off the scalp. Most people have never considered this, but practising this simple routine can improve scalp health and leave hair easier to manage."

In a nutshell, pls...

Basically, the number of times you wash your hair a week is a pretty personal decision and it really depends on your hair type and scalp. However, there is such a thing as over-washing your hair. This strips the scalp of all its natural oils (not good - a little bit of oil build-up is healthy for your scalp). In turn, this can leave your scalp dry and flaky. 

There is also such thing as not washing your hair enough. This can bring with it a whole heap of annoying of issues such as scalp inflammation and sores. 

Our advice? Find that sweet spot. If you're experiencing any issues with your scalp - you'll know something is up.

Feature image: Getty

How often do you wash your hair? Share with us in the comment section below.