An Expert Explains Why Your Hair Gets Greasy Overnight and What to Do About It

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Do you fall asleep with freshly-washed strands only to wake up to them being oily in the morning? Are you struggling to understand why hair gets greasy overnight? This incredibly frustrating problem is all too common for some.

Kate Holden, consultant trichologist, has some answers and advice for you. The founder of Kate Holden Clinic in Manchester can tell you why your hair gets greasy when you sleep and what you should do about it.

Keep scrolling to read what she had to say!

Why does hair get greasy overnight?

“Our hair gets greasy when there is a build up of a natural oil on the scalp called sebum,” Kate shares. “Sebum is produced by our sebaceous glands and functions to lubricate and waterproof the skin and hair, which is essential for maintaining a healthy hair and scalp. Our sebaceous glands are working all the time. But if you’re noticing that your hair gets greasy overnight, that indicates that your glands may be overactive or you need to adjust your haircare routine.”

There is also a laundry list of more common reasons for this problem. An increase in extra oil can be caused by “hormones (think puberty, periods and menopause), diet, genetics, medications, changes in the environment, and your haircare routine.”

Sleeping habits can often be to blame for greasy hair. This is especially true “if you’re not washing your pillowcases often enough.”

There are also a number of ways your hair washing routine contributes to extra oil production.

“How you wash your hair can definitely contribute to an oily scalp,” Kate says. “Washing your hair too often can cause your scalp to overproduce sebum. Not washing your hair enough will cause a buildup. Washing your hair two to three times per week is recommended to get a good balance.”

You should even be weary of how hot the water is.

“Washing your hair in hot water also stimulates the sebaceous glands, so turn the temperature down on your shower to prevent this,” Kate notes.

And though it feels amazing, Kate mentions massaging your hair for too long can contribute to oily strands.

“Massaging the scalp can activate the sebaceous glands too so try not to massage for longer than one minute,” she notes.

Woman looking at the camera while laying on her bed and running her fingers through her hair
(via Unsplash)

Could it be a sign of a major underlying condition?

Kate assures us that “most of the time, greasy hair is nothing to worry about.” There is one instance, however, when it should raise a bit of concern.

“If you are dealing with greasy hair every day, no matter what you try, then it might be a symptom of an underlying hormone imbalance such as PCOS. If you are worried that your greasy hair is a symptom of a medical condition, speak to your general practitioner, trichologist, or dermatologist.”

What can you do to prevent hair from getting greasy overnight?

Luckily, there are a number of things you can do to decrease overnight oil production.

“I would recommend avoiding hot showers or baths before bed; using a shampoo designed for greasy hair; applying dry shampoo to the roots; tying your hair up to prevent the sebum traveling down the hair shaft; and making sure you’re washing your pillowcases regularly to prevent buildup of grime and sweat,” Kate shares.

Kate also recommends a few products that’ll help with yoru problem.

“When you’re looking for a clarifying shampoo, you need a stronger surfactant (cleaner) to remove the oil from the hair and scalp,” she says. “In terms of dry shampoo, Batiste is my usual go-to. If you find aerosol-based dry shampoos too drying, you can get them in powder form. For example Lush does a powder dry shampoo. When you tie your hair up at night, I’d recommend a soft scrunchie, fabric hair tie, or head scarf to reduce friction on the hair shaft.”

It’s also important to look at your diet as a cause for excess oil production.

“If you have a diet which is high in refined carbs and saturated fats, then this might be contributing to your greasy hair,” Kate mentions. “Swap out the refined carbs to wholegrain and the saturated fats with unsaturated fats. Also, make sure you’re eating lots of fruits and vegetables.”

After making these changes, you should quickly notice your hair being less greasy when you wake up. If the problem does persist, be sure to reach out to a professional.

Girl sleeping on a blue pillow
(via Unsplash)

Struggling with freshly-washed strands that look greasy? HERE is what you should do to fix that problem.