If you're scratching your head over what's causing your itchy scalp, it's worth noting that flaky and inflamed skin on this part of the body affects most women at some point. So while thoughts automatically turn to a head lice infestation, the reason for your discomfort could be anything from dandruff to an allergic reaction.
We rarely think about our scalps as being an extension of the skin on our foreheads, largely because we can't see it. Out of sight, out of mind, really does apply here. But Anabel Kingsley, brand president and trichologist at Philip Kingsley, says we would be remiss to ignore an itchy scalp or any other symptoms that suggest it has been thrown out of whack.
“A scalp condition needs consistent treatment and care to help to bring it under control, in the same way as a skin condition,” Anabel explains, adding: "You would prevent yourself from scratching and itching your skin on your face or body, and you should try to do the same with your scalp.”
As ever, identifying the root cause is the first step to less inflamed skin and being back on good terms with your hair. With the help of a panel of experts, we reveal the 14 reasons your scalp may be itchy – and how you can rectify it.
1. Dandruff
Dandruff is one of the most common reasons why people have an itchy scalp. Contrary to popular belief, though, dandruff is not caused by dry skin, so applying a trusty hair oil will only make matters worse. “Dandruff is almost always oily," says Anabel. "So applying hair oils in a bid to clear it simply results in stickier, greasier flakes.”
A yeast-like fungus called Malassezia is responsible for the snowy white flakes that drift down and settle on your shoulders. There are many over-the-counter products laced with antimicrobial agents, such as piroctone olamine, you can use to treat dandruff, including the Philip Kingsley Flaky/Itchy Scalp Anti-Dandruff Shampoo.
Hair stylist Kala Kilshaw recommends choosing a shampoo containing zinc (Redken Scalp Relief Dandruff Control Shampoo, is good) to help relieve the itchiness. She also maintains that not going to bed with damp hair will help to prevent scalp fungus and irritation.
2. Psoriasis or eczema
Another common cause of an itchy scalp is psoriasis or eczema, which are inflammatory skin conditions that can appear on the scalp. “They're not contagious and can't spread from person to person," says Wil Fleeson, owner of Rainbow Room International's Stirling and Buchanan Street Salons and director of Trichology Scotland.
"However, you can be more likely to develop psoriasis or eczema if someone in your family has it. Both conditions cause red, scaly and itchy patches on the scalp, but, like dandruff, these conditions can be treated to reduce the symptoms,” he continues, adding that you should always visit a trichologist to work out the correct treatment plan based on the severity of your condition.
3. Dry scalp
Another common cause of itchiness is a dry scalp, which is more common during the winter months when you are moving between the cold weather outside to a centrally heated house. “Harsh weather conditions can strip the scalp of its natural oils, so make sure you use hair products, particularly conditioners and hair masks with the word ‘hydrating’ in the product description,” says Wil.
Dial down the temperature of heated styling tools, too, as volcanic temperatures from your blow dryer and tongs can dry out the scalp.
4. Allergic reaction
Fragrance is often an allergen, but your diet can also be a factor. “Similar foods that affect the skin on your face also impact your scalp,” Anabel says, noting that the main culprits are dairy products and very sugary and spicy foods. “Other scalp aggravators are white wine, champagne and red peppers,” she adds.
Trigger foods aren't the same for everyone, so it may be a case of working out yours based on a process of elimination.
5. Head lice
Head lice or nits are tiny eggs that attach themselves to your hair strands and are usually picked up from head-to-head contact. “With hair lice, the key is to treat them as soon as you spot them and there are plenty of products on the market that can help to get rid of them, including medicated lotions and sprays, tea tree oil remedies and special head lice combs [try Nitwits All-In-One Headlice Solution],” says Wil.
6. Hard water
The build up of minerals such as calcium and magnesium found in hard water, produces a film on the scalp that blocks the follicles. This makes it difficult for moisture to get through and can lead to itchiness and inflammation. Try the Act + Acre Cold Processed Scalp Detox – a pre-cleanse oil, which breaks down build-up, delivers nourishment directly to the hair follicle and stimulates blood flow for hair growth via basil leaf extract.
7. Atopic dermatitis
Skin that shows up as red and itchy could be atopic dermatitis, a skin condition that also typically affects the elbows and backs of the knees. Atopic dermatitis is usually genetic but it's worth avoiding fragranced hair products, which could exacerbate the symptoms. Also invest in a super hydrating conditioner or hair mask for added relief.
8. Scalp ringworm
Scalp ringworm appears as a round patch with raised borders and is caused by a contagious fungal infection (often transferred from a pet). Your GP will be able to determine whether you need oral or topical anti-fungal medication.
9. Product build-up
Product buildup can make your scalp really dry, itchy and irritated. Many hair styling products, shampoos and conditioners contain allergens and irritants and the longer these are left on the scalp, the more likely they are to cause flare-ups.
“Product build-up can also interrupt your natural shedding rate,” warns Wil. “Naturally, we should lose between 50-100 hairs a day, but product buildup can interrupt this natural shedding process and cause hair to become dry, flaky and itchy. To avoid this, try to stay away from using too many styling products on your hair, particularly those that contain silicones.”
Also beneficial is adding a clarifying shampoo such as Bumble & Bumble's Sunday Shampoo, £20 or K18 Peptide Prep Detox Shampoo into your weekly hair routine.
10. Overuse of dry shampoo
Infrequent shampooing – as in lathering up with water – can cause a build up of dry shampoo on the scalp's surface. “Like the skin on your face, your scalp sweats, contains sebaceous glands and sheds dead skin cells,” Anabel says. “Unlike an actual shampoo, which is rinsed away with water, dry shampoo does not remove dirt and product debris.” According to Anabel, the longest you should rely on dry shampoo is a day or two.
11. Seborrheic dermatitis
According to the Mayo Clinic, a telltale sign of seborrheic dermatitis is greasy skin covered with flaky white or yellow scales and stubborn dandruff. It usually affects oily areas of the body and is a common skin condition that mainly affects your scalp. Although irritating, it's not contagious – your local pharmacist may just recommend using a medicated shampoo to clear up symptoms.
12. Skin cancer
If skin cancer develops on your scalp, it may itch. “Your scalp can burn, just like the skin on your face,” warns Anabel. “While this can lead to short-term effects of discomfort, flaking and peeling, repeatedly exposing your head to the sun may result in serious changes on a cellular level, such as skin cancer.”
If you're concerned, Anabel recommends seeing a board-certified dermatologist, who will examine your scalp and determine whether you need to be tested for skin cancer or if something else may be causing the itch. “You can also use daily protective sprays containing PABA sunscreen to mitigate damage caused by the envrionment, such as the Philip Kingsley Daily Damage Defence,” she adds.
13. Transepidermal water loss (TEWL)
If you find the itching gets worse at night, it's most probably the result of physiological changes to your skin. For example, skin is more permeable overnight, so your scalp may be suffering from transepidermal water loss, a phenomenon where water evaporates from the skin, leaving it feeling drier. Your levels of anti-inflammatory hormones (corticosteroids) also naturally drop overnight, which may exacerbate itchiness.
14. Iron deficiency
It's well-known that an iron deficiency can impact hair growth but a lesser-known side effect is an itchy scalp. While the exact reason is currently unknown, low iron levels are thought to make the skin thinner, causing more water loss.
“Physiologically, hair is not an essential tissue so it is the first part of the body to be withheld from, and the last to benefit from, what we eat," says Anabel. Good ways to supplement include JS Health Iron + High Absorption and Dr Barbara Sturm Growth Cycle Hair Supplement.
