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Greasy Hair Causes
Greasy Hair Causes


Greasy Hair Causes: Why is My Hair so Greasy?

Constantly finding that your hair looks greasy can be frustrating – especially if you don’t know why. You can feel trapped in a never-ending cycle of dealing with bad hair days and all too frequent hair washes. So, why does your hair get greasy after just one day?

Our scalps contain sebaceous glands, which produce a natural oil known as sebum. Sebum production is perfectly normal – as it helps to moisturise your hair and scalp – but if your sebaceous glands start to overwork, they can end up producing too much of this natural lubricant. This excess oil can lead to a greasy scalp and hair.

In this article, we’ll cover what causes greasy hair, and more importantly, what solutions you can try to overcome it.

What does greasy hair look like?

If you’re wondering how to tell if your hair is greasy, here are some key characteristics to look out for:

  • Dull hair
  • Greasy scalp
  • Limp and lifeless strands
  • Little volume around the roots
  • It’s knotty and more difficult to manage.

What causes greasy hair?

Oily and greasy hair can be caused by many different things, from the way you wash your hair to the products you use . Here are some of the most common causes of greasy hair:

Over brushing your hair

If your hair is looking greasy, you may try to style or brush it, but overbrushing or brushing too hard can actually over-stimulate the sebaceous glands in your scalp. This can carry oil from the scalp to the rest of your hair and cause your hair to become greasy faster than usual.

Touching your hair too much

While it can be tempting to touch or play with your hair frequently – just like with brushing – you could be unintentionally spreading oil from the scalp to the rest of your hair. It’s also possible to spread oil onto your hair from your fingers too, making it look greasy more quickly.

Using the wrong products

Think about what products you regularly put in your hair. Using too many products, or the wrong type of product, can lead to product build-up, and make your hair look even more greasy.

Excessive washing

Over-washing can make your hair look greasy because it strips the hair of its natural oils. This loss of natural oils causes the body to overcompensate by producing more sebum. Over-conditioning can also lead to greasy hair because it weighs down the hair and this in turn increases oil production.


Oil and sebum production can be affected by different hormones in the body. Therefore, factors like taking contraceptive pills and stress levels, which affects your hormones, may also contribute towards oily hair.

Skin or health conditions

Certain skin or health conditions can be responsible for greasy hair. For instance, some people may find they have overactive sebaceous glands. This can result in excess oil on the scalp, attracting debris, clumping hair together and increasing dandruff.

How to address greasy and oily hair

Once you’ve identified the potential causes for your greasy hair, you can start looking for solutions. Read on to explore some effective remedies that could work for you and your hair.

Change your shampoo routine

Changing the way that you wash your hair can make a big difference to the appearance of oily hair. Aim to shampoo your hair more or less frequently as needed – around one to two times a week is generally recommended for most hair types – or use shampoos made for oily scalps. NEUTROGENA® T/Gel® Anti-Dandruff Shampoo for Oily Scalp is specifically designed for greasy hair and works by removing excess oil.

Be gentler with your hair

The way you physically handle your hair will affect how greasy it becomes. To avoid overstimulating your sebaceous glands, try to minimise touching and brushing your hair. When you do brush, do it gently and try not to touch your scalp with the brush to prevent oil from moving through the hair.

Learn to manage your stress

Stress levels can be the cause of many health problems – greasy hair included – and learning to manage stress can help balance oil secretions. If you want to reduce your stress levels, you could try these helpful practices:

  • Recognise your triggers
  • Exercise regularly
  • Practice breathing techniques
  • Connect with loved ones

Change your bedding regularly

Your pillowcase absorbs oil from your face while you’re sleeping, which can pass onto your hair as you move in the night. It’s important you wash and change your pillowcases and sheets regularly to help reduce greasy skin and hair.

Eat a balanced diet

Maintaining a healthy diet isn’t just important for your hair, but your health in general. An unbalanced diet can lead to a wide variety of health problems, so remember to eat the right foods, and drink plenty of water too.

If you notice persistent oiliness, irritation, or inflammation around your scalp, speak to a doctor for advice.

Greasy and oily hair: FAQs

Does washing your hair with just water make it greasy?

Washing your hair with the right products will help to keep it looking healthy and grease-free. When washing your hair, dermatologists recommend applying shampoo directly to the scalp. When it comes to using conditioner, this can be applied after each shampoo, but should be only used from the mid-length to the tips of the hair rather than the scalp.

Why does my hair get greasy overnight?

Hair can become greasy quickly if you are spreading the oil from your scalp onto your hair. This can happen at night through contact with pillows, so frequent washing of your bedding is important. Additionally, if you’re not using the right shampoo or effectively washing away sebum from your scalp, it could cause the hair to look greasy not too long after washing. Look out for shampoos made for oily hair to help with this.

Is it good to let your hair get greasy?

It’s best to prevent your hair from becoming too greasy to keep the scalp healthy. Sebum is the natural oil produced by the scalp that helps keep the skin moisturised and healthy. However, if the scalp starts to become built up with excess oil and grease, this can lead to itching, redness, and dandruff.

Does sweat make your hair greasy?

Yes, sweat can make your hair greasy. If you exercise a lot, it’s recommended that you wash your hair more regularly to help clear out the sweat and grime and keep it looking grease-free.

Can greasy hair cause spots?

Keeping greasy hair away from the skin can help to prevent spots. Remember to keep oily hair out of contact with your face and use oil-free hair care products to prevent pores becoming clogged.

Does greasy hair cause dandruff?

Yes, in some cases greasy hair can lead to dandruff. The over production of oil on the head can block the hair roots and attract fungal growth, which may lead to dandruff and even hair loss.

Can greasy hair cause a sore scalp?

If you have greasy hair and find you’re having to wash it every day, you may be drying out your scalp. Choose a shampoo for daily use containing Sodium Laureth Sulphate – such as our NEUTROGENA® T/Gel® Anti-Dandruff Shampoo for Oily Scalp – which are effective products for oily scalps.

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