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Does Not Washing Hair Cause Hair Loss? What Science Says
Dr Meena Zareie (GMC)
Medically reviewed by
Dr Meena Zareie (GMC)
Updated on December 5, 2024

Does not washing hair cause hair loss? There’s a lot of debate around how often you should wash your hair to keep it strong and healthy [1]. Some believe washing your hair everyday can make your hair fall out, while others worry that not washing your hair will cause hair shedding.

So what’s the truth? Does not washing your hair cause hair loss? In this article, we’ll explore:

  • Whether not washing your hair can cause hair loss
  • How often to wash your hair to prevent hair loss and encourage growth
  • The benefits and disadvantages of regular hair washing
  • Hair loss causes and treatments 
Table of Contents

Does not washing hair cause hair loss?

While the research into hair washing frequency and hair loss is minimal, one study has found that low wash frequency may be associated with increased hair loss [1]. That’s because washing your hair less often can increase sebum (the natural oil produced by your scalp) and scalp sensitivity.

This chart shows how hair loss and texture can be affected by wash frequency. Washing your hair less than once a week resulted in the highest levels of perceived hair loss:

Can not washing hair cause hair loss
Effect of wash frequency on hair issues, from study [1]

Meanwhile, daily washing resulted in the lowest perceived rates of hair loss. This suggests it’s better to wash your hair more frequently if you’re concerned about hair loss.

While hair texture is affected to a lesser extent, this also suggests hair that’s washed more often is less brittle (although hair smoothness is associated with less frequent washing).

Although this study did not address actual rates of hair loss, the researchers observed no negatives to hair condition as wash frequency increased. The trend indicated that hair issues decreased as wash frequency increased.

Lower shampoo wash frequency may also lead to conditions like dandruff [2]. It can also lead to seborrheic dermatitis, particularly in those with Afro hair.

How often should you wash your hair?

Washing your hair regularly keeps it clean and promotes good scalp health. Most people should wash their hair at least every two to three days.

How often you wash your hair can depend on your hair type, texture, and styling preferences. Those with tightly coiled hair may find their hair becomes drier with more frequent washing.

Additionally, if you’ve had chemical treatments or a hair transplant, you may be advised to wash your hair on a specific schedule. Find out more about washing your hair after a hair transplant.

It may seem like washing your hair makes your hair fall out in the shower. But remember that it’s normal to lose some hair: people with healthy hair lose up to 100 hairs every day, many of which are loosened and removed in the shower [3].

What do 100 hairs look like
100 hairs from a person with short hair (left) and longer hair (right).

However, if you see a sudden or gradual increase in the amount of hair coming out in the shower, you may have a hair loss condition. Note that this probably isn’t triggered by hair washing — it’s much more likely to have another underlying cause.

How often should you wash your hair if you have alopecia?

If you’re already seeing the early signs of hair loss, it can be tempting to avoid washing your hair or reducing wash frequency to prevent more hair coming out in the shower.

Unfortunately, not washing your hair won’t stop your hair falling out if you have male pattern baldness. Your hair will shed regardless of whether you wash it, and as the research shows, washing your hair regularly may actually reduce hair shedding.

If you’re concerned about hair loss, consider switching to a medicated shampoo to help minimise shedding and promote regrowth. The following options may improve symptoms of hair loss:

Is it better to go longer without washing your hair?

No, it’s generally better to wash your hair more often. One study found that increasing hair wash frequency could result in less flaking, redness, itchiness, and scalp fungi that lead to dandruff and other scalp problems [1].

What happens if you don’t wash your hair for 3 weeks?

Not washing your hair for three weeks or more will result in a buildup of oil, grease, and hair products on your scalp. This can make your hair look greasy and may make your scalp feel tender, itchy, and even painful.

This image shows the difference in buildup after a week of not washing your hair vs daily washing:

Not washing hair for a week

The “no-poo” hair washing movement is growing in popularity. This involves washing your hair with products other than standard shampoos, such as baking soda, apple cider vinegar, or just water.

However, there’s currently no evidence that this removes scalp buildup effectively, or that it’s better for your hair and scalp than regular shampoo. Also, bear in mind that while hard water doesn’t necessarily cause hair loss, it may not be good for your hair. So consider the softness of your water before opting for a no-poo method of washing.

Can a dirty scalp cause hair loss?

While having an unclean scalp can feel uncomfortable, it’s not a direct cause of hair loss. However, scalp buildup can cause infection that leads to folliculitis, or hair follicle inflammation [4]. Severe folliculitis may result in hair loss and even scarring on the scalp, so regular hair washing is important to remove excess oil and scalp buildup.

How often should you wash your hair for hair growth?

Research shows that washing your hair more frequently is less likely to result in hair loss. But how often should you wash your hair if you want to stimulate growth?

Unfortunately, there’s limited research into wash frequency for hair growth. But it appears that more frequent washing is better for hair in general, so it’s a good idea to wash your hair at least once every two to three days to keep your hair and scalp healthy. If you’re using a medicated shampoo, use it as instructed by your doctor.

Does no shampoo cause hair loss

Benefits of not washing your hair

According to research, there aren’t many health benefits of skipping your regular hair wash. However, there are some reasons why you may choose to do so. These include:

  • Colour fading — Regular washing can cause dyed or coloured hair to lose its colour faster. For this reason, some dye companies recommend reducing your wash frequency to make their products last longer. 
  • Saving time — Washing your hair tends to take longer than a quick body wash, especially if you have long hair that needs shampooing and conditioning. Reducing hair washes may save you time.
  • Saving money — More frequent washing means you use more shampoo and conditioner, as well as possibly increasing your water bill. 
  • Environmental impact — Longer in the shower means you’re using more water, which may be a particular issue in areas with a general water shortage. 
Not washing hair can cause itchy scalp

Disadvantages of not washing your hair

While some of those reasons may make you think twice about washing your hair more regularly, it’s important to think about your health as well. Here are some of the reasons you might not want to ditch the shampoo: 

  • Preventing buildup on your scalp  — Repeatedly skipping shampoo hair washes can cause oil and hair products to build up on the surface of your hair. This can feel uncomfortable, may make your scalp more sensitive, and may not smell pleasant. 
  • Preventing hair loss — Research suggests regular hair washing may help to prevent hair loss, although further research is needed on this topic. 
  • Avoiding common scalp problems — Washing your hair with shampoo less often may lead to conditions like seborrheic dermatitis, dandruff [2], flaking, redness, hair follicle inflammation [4], and cause an itchy scalp [1]. 

Ultimately, there’s a balance to strike between the two. For this reason, hair washing is usually recommended every 2-3 days rather than every single day. 

Causes of hair loss

What causes hair loss?

Those who don’t wash their hair often may see more hair shedding than those who give their scalp a regular scrub. But it’s unlikely that this is the only or even main cause of hair loss.

Some common causes of hair loss include:

Balanced diet for healthy hair

Ways to tackle your hair loss

Hair loss can be distressing and affect your self-confidence. Fortunately, there are several treatments that may help restore your locks to their former glory. Here are some options: 

Getting expert help for hair loss

Getting expert help for hair loss

If you’re not sure what’s behind your hair loss, it’s time to speak to a trichologist. Consider speaking to your GP to rule out any underlying conditions, then book a consultation at one of our clinic locations to get a diagnosis and treatment plan. 

Our expert hair doctors can use diagnostic trichology tests, such as hair loss blood tests or a hair pull test, to identify the reason your hair is falling out. They can also provide specialist advice on how often you should be washing your hair and the best hair loss products for your needs. 

Does Not Washing Hair Cause Hair Loss? What Science Says, Wimpole Clinic

Frequently Asked Questions

Washing your hair with just water won’t hurt it occasionally, but a good cleansing shampoo is needed to remove the buildup of oil and products that can gather on your scalp. Skipping shampoo may lead to scalp conditions and even hair loss further down the line. 

There’s no evidence that not washing your hair makes it thicker — in fact, it may have the opposite effect. For thicker hair, consider hair thickening products, medication like minoxidil, or permanent hair transplant

It depends on the cause. But in many cases, thinning hair can be reversed with an effective treatment plan. Speak to a trichologist to identify the cause of your hair loss and get started with a plan to reverse it.

Good news — it’s totally fine to wash your hair in hot water, and this shouldn’t cause hair loss or balding. However, boiling hot water could burn your scalp and cause hair loss, so be careful not to crank the temperature up too high. Washing hair in scalding water is uncommon, but it’s something to be aware of if you have reduced sensation on your scalp. 

Dr Meena Zareie (GMC)
Medically reviewed by Dr Meena Zareie (GMC)Updated on December 5, 2024
The Wimpole Clinic offers FUE Hair, Beard & Eyebrow Transplants & Trichology.
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