This Is Why Your Hair Is Always Greasy (& How You Can Stop It Happening)

Dear Daniela,
As a hormonal teen, I dreamed of the day I'd become a 'grown-up lady' and escape my problem skin and greasy hair. Unfortunately, at the ripe old age of 34, as an endometriosis and PCOS sufferer I'm still a victim of my raging hormones and my hair needs washing every day. If I skip a wash, by day two it is noticeably greasy and needs a liberal dousing of dry shampoo. By the third day, it hangs in thick, lank, greasy clumps, way beyond help. I'm desperate to find a decent everyday clarifying shampoo that can finally tame my oily locks and help my hair last longer between washes. Ideally I'm looking for something eco-friendly and free from parabens, silicones, sulfates and phthalates, too. But I might be asking for a miracle!
Rachael, 34
I take no pleasure whatsoever in your predicament. That being said, I really cannot pass up an opportunity to talk about one of my top five favourite beauty topics: scalp care! (The other four are SPF, retinol, highlighters that look dewy but not sparkly and really ridiculously luxurious body creams.) Essentially, I don’t think the problem is your hair per se. I think it’s your scalp.
I understand that sounds like a bit of a cop-out and that you’re probably thinking, Hair, scalp, potato, poh-ta-to, right? Well, they do get washed together, but in cases like this I think it’s worth remembering both of these entities for what they are: skin and hair respectively. They obviously have a synergistic relationship but the root cause (pardon the pun) of your problem lies with your scalp and not your hair. Your scalp is just skin – the very same skin that’s on your face – so if you struggle with oiliness on your complexion, it stands to reason that your hair will, too.
"There are comparatively more sebaceous glands on the scalp than the face," explained trichologist Zoë Passam at the Philip Kingsley Clinic, and this is thanks to the innumerable hair follicles themselves. "Sebum production is primarily under the control of androgens (male hormones), with higher levels increasing sebum production. The surge in androgen production in puberty is what gives you the typical greasy hair of adolescence. This usually tapers off as the hormones settle down, but in individuals who are more sensitive to androgens, the oiliness may persist," she added. That’s where your PCOS comes in – but you didn’t need me to tell you that.
So, what to do? I think you’re a prime candidate for a scalp toner. Used after washing, one with slightly astringent properties can help control oil production and keep your hair feeling cleaner for longer – Passam suggested witch hazel as a good ingredient, and Philip Kingsley Scalp Toner is a brilliant place to start, with the aforementioned witch hazel and menthol to refresh and soothe. You could also try adding in a weekly scalp deep cleanse with the Bumble & bumble Scalp Detox, a mousse that uses micellar technology to lift away debris and which has a very pleasing cooling effect on the scalp.
Unfortunately, you’re most likely never going to be one of those people who can eke out a blow-dry for four days, but that’s no bad thing, as your regular washing is definitely helping. "Studies have shown that the rate at which sebum is removed from the scalp has no bearing on sebum production, so shampooing more often will not make your hair more greasy. Ensuring the hair is thoroughly wet prior to applying shampoo will also allow the shampoo to work more effectively," Passam explained. If you really can’t bear it some days (and I don’t blame you for that, hair washing and drying is arduous), the Klorane Dry Shampoo with nettle is a good stopgap, helping to absorb oil without any talc.
Shampoo-wise, I think a clear shampoo will usually be a good shout for you to avoid it being too moisturising and heavy, and I’ve really enjoyed the Kérastase Micellar range. You mentioned in your longer letter that you wanted to avoid 'chemicals', and while that’s totally your prerogative, seeing as all hair is dead keratin, I personally care a lot less about the use of silicones or what have you on my hair than I do on my skin. Just a thought!
Otherwise, be super scrupulous with your shampooing, take time for scalp treatments and keep conditioner for the lengths and ends of your hair only. Once you get the oil under control through shampooing and toning, you’ll find it easier to build manageable volume without the grease to weigh you down.
Good luck!
Got a question for our resident beauty columnist Daniela Morosini? No problem, qualm or dilemma is too big, small or niche. Email, including your name and age for a chance to have your question answered. All letters to 'Dear Daniela' become the property of Refinery29 and will be edited for length, clarity, and grammatical correctness.
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