Allure Podcast

The Science of Beauty: The Complete Guide to Scalp Care

On this episode of The Science of Beauty podcast, we break down how to care for your scalp and share the best ways to tackle oiliness, itchiness and — of course — dandruff. (Available on Apple Podcasts, Spotify, or wherever you listen to podcasts.) This episode made possible by Pantene.
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It’s easy to overlook what you can’t see, which is why so many of us ignore an area on our bodies that’s generally out of sight: our scalp. But lack of care can lead to the onset of conditions that will definitely demand your attention: Since the scalp is really just an extension of your face, it too is susceptible to irritation, itchiness, and dryness. (And then of course there’s everyone’s favorite — dandruff. So in effort to spread the word about how to fend off these pesky problems — and in turn, create a healthier environment in which hair can flourish — we dedicated an entire episode of The Science of Beauty to how to tend to your scalp.

Our co-hosts Michelle Lee, editor in chief, and Jenny Bailly, executive beauty director, tapped two experts to get the job done. You can read on for a compilation of their top tips — but if you want to hear a rather, uh, vivid description of every nook and cranny on Jenny’s scalp as seen through the microscopic lens of consulting trichologist David Adams, you’ll just have to tune into our episode.

First, what does the scalp do?

You might think the skin that comprises the scalp is vastly different from the skin on the rest of our bodies because it grows thicker, longer hair. But in fact, the scalp is anatomically similar to the rest of your skin, just with a little extra density (it’s made up of five different layers of tissue while the rest of our skin has three), more oil glands, and a ton of hair follicles — about 100,000 to be exact.

Each hair grows from, and through, an individual follicle located within the scalp. Sebum (also known as oil) is produced by the sebaceous glands in each individual follicle and helps condition the hair and surrounding skin. The amount of oil produced on the scalp varies from person to person, with some experiencing much less (or much more) than others. At the base of the hair follicle are sensory nerves that wrap around each hair bulb; pulling the hair stimulates these nerve endings and alerts us to feelings of pain.

The purpose of the scalp isn’t just to produce hair; it also serves as a physical barrier to protect the skull from trauma and infection. So, the scalp serves both a functional purpose as well as an aesthetic one. (And if you’re interested in learning more about why our scalp sprouts more noticeable hair than, say, our legs, you’ll get your fix during next week’s episode on body hair.)

What does a healthy scalp look like?

“We shouldn't see redness, we shouldn't see irritation, and we shouldn't see a lot of scales or buildup,” says dermatologist Michelle Henry during the podcast when asked about the signs of a happy, highly functioning scalp. “It should not feel tender and it should not have an odor.” If your scalp has any of these problems, the issue could be as basic as a reaction to a heavily-fragranced shampoo or as complex as an autoimmune condition. That’s why Henry says it’s always best to see a dermatologist about scalp concerns.

How should you care for your scalp?

The same basic principles of skin care generally apply to scalp care, as well. Consistently removing debris, dirt, and oil on your scalp is vital, as is hydrating it. And just like your skin-care routine, your scalp-care routine should be reflective of the condition of your scalp. If yours tends to be dry, for example, avoid overstripping it with harsh scrubs.

But universally, the path to proper scalp care begins with removing debris and product build-up with shampoo. (We know you already know all about that, having listened to episode number seven.) Trichologist David Adams suggests brushing your hair before you get in the shower to suds up, to help loosen debris so it can be easily rinsed away.

While shampooing properly is important for any scalp, there are some differences in caring for a dry one versus an oily one.

How to Care For a Dry Scalp

In a dry scalp, the skin gets irritated and flakes off because it doesn’t have enough oil and moisture. People with dry skin are also prone to dry scalp and both problems are usually caused by the same factors, such as genetic predisposition, dry air, excessive washing, and older age.

Adams recommends that those experiencing dryness consider a scalp toner, since many are formulated to be moisturizing. His personal favorite is Philip Kingsley Flaky Scalp Calming Scalp Toner with aloe vera and camphor.

If you’re experiencing dryness, it’s also important to wash with a gentle, moisturizing shampoo, followed by a moisturizing conditioner. Try to shampoo your hair less frequently and use warm water instead of hot water. Running a humidifier is another way to prevent dehydration.

How to Care For an Oily Scalp

While the amount of oil produced by follicles varies from person to person, those with certain hair types can actually appear to have oilier hair and scalps than others, even if their follicles are secreting the same amount of oil. “If you have fine, straight hair, that little blob of oil [that the glands of the scalp produces] is going to shoot right down to the tip of the hair and it's going to make it oilier,” explains Henry. “If you have kinky, curly hair, that means that little blob of oil has to make its way down that tight coil and that hair tends to be a little bit drier.”

The first step to care for hair that’s on the oilier side is to shampoo more frequently. But resist the urge to regularly use clarifying shampoos. Instead, wash with a gentle, sulfate-free shampoo one day, and one that exfoliates the scalp the next (look for formulas that incorporate tea tree oil or salicylic acid).

Also, scalp exfoliators containing physical exfoliants like sea salt work great to remove the debris and buildup that often accumulate on an oily scalp, says Henry.

How should you treat scalp conditions?

Certain scalp conditions can result in hair breakage and even hair loss, so it’s vital to take the signs — like redness, irritation, and itchiness — seriously. A dermatologist can help correctly diagnose what may be going on, and outline the best treatment options for you.

What Is Dandruff and How to Treat It

Often mistaken as a symptom of dry scalp, dandruff — the shedding of skin cells from the scalp at an unusually high rate — is typically coupled with excessive oil production and the presence of a yeast-like fungus. Unfortunately, dandruff is an intermittently chronic condition and may never disappear permanently. And while anyone can get dandruff, some are more prone to it. It usually starts in puberty and tapers off after the age of about 50, and it’s more common in women than in men.

Here’s the good news: Mild to moderate cases of dandruff can usually be treated at home with shampoos that contain ketoconazole, selenium sulfide, or zinc pyrithione. These ingredients have antifungal and antimicrobial properties, which allow them to reduce flake-causing fungus growth on the scalp. Salicylic acid shampoos are also used to help eliminate flakes.

Keep in mind that the fungus that causes flakes can regrow on the scalp fast, so use dandruff shampoo daily when you have a flare-up, and weekly after that. And don’t just immediately wash it out. Instead, allow enough time for the active to do its thing and massage the formula into the scalp for a few minutes. Experts say to avoid hair styling products for the first few weeks of treatment, since these products can leave a buildup that blocks active ingredients in your treatment products.

What Is Scalp Psoriasis and How to Treat It

Psoriasis is a condition that causes scaly patches on the body — including the scalp. Psoriasis is thought to be an immune system problem that causes skin cells to regenerate too quickly, forming in days instead of weeks. The body does not shed these excess skin cells, so they pile up on the surface of the skin and cause patches that are often red and itchy. Scalp psoriasis can look a lot like dandruff, as the scales often produce flakes, but they are two distinct issues. Only a doctor can accurately tell you which one you’re dealing with.

Over-the-counter and prescription products can help manage symptoms; they include shampoos, topical steroids, and oral treatments like methotrexate. The two active ingredients that you should look for in OTC shampoos are salicylic acid and tar (either coal or wood tar). Salicylic acid works to soften plaques and scales and ultimately remove them from the skin, while tar made from coal or wood works to slow skin cell growth and reduce inflammation and itching.

What Is Scalp Eczema and How to Treat It

A common form of eczema, atopic dermatitis is a chronic condition that can appear on the scalp and typically begins in childhood.

Although the underlying cause is still unknown, the immune system becomes overactive and triggers an inflammatory reaction, leading to dryness and itchiness. Topical corticosteroids and other lotions, such as pimecrolimus or crisaborole, are common treatments. Oral antihistamines or prescription corticosteroids, such as prednisone, can also be used to control the condition.

Again, many of the symptoms of atopic dermatitis overlap with those of other conditions — so it’s important to get an official diagnosis from a dermatologist before attempting to treat it.

What to Do If You Notice Hair Loss

This is arguably the most distressing scalp issue of them all — significant hair shedding. “The first thing is to get the right diagnosis,” says Henry. “ If we have a medical condition, we often shed our hair because our body needs to function on more vital things.” If you're experiencing excess shedding, head to the doctor to make sure that your thyroid, an autoimmune disease, or a lack of certain vitamins isn’t behind your hair loss.

That said, some hair loss can be linked to the way hair is worn. “It's called traction alopecia,” explains Henry. “We see it in anyone who's wearing a style repetitively that might be a little bit tight. That tension causes inflammation in the scalp, and inflammation causes hair loss.” Henry notes it’s common in the ballet community, as dancers often wear high, tight buns as part of their job.

Henry also offered her own experience: “I’ve had braids [throughout] my entire life,” she says on the episode. “There should not be a period after you have your braids or your weave that it feels uncomfortable — that you can't sleep on it well, that you have to take a Tylenol. We should normalize…. having that conversation with your stylist [about your braids being too tight].” This type of damage can also lead to what’s called central centrifugal cicatricial alopecia (CCCA), a chronic condition characterized by scarring on the scalp which in turn causes permanent hair loss. Henry has said it’s most prevalent in people of color, particularly Black women.

So loosen up your hairstyle and rule out any health issues with a visit to your doctor. Then you can explore ways to regrow your hair — options for which can range from supplements to OTC products with minoxidil, to laser or light treatments or even hair transplants.

Regarding that last option, doctors are currently able to move your own follicles from one area of your head to another to help camouflage hair loss. But Henry mentions on the podcast that researchers are working on ways to actually create more follicles — meaning you won’t have to sacrifice the hair on the back of your head for a fuller look at the crown.

Our Hosts’ Favorite Scalp Products

Michelle’s Current Favorites

Michelle admits she just recently got into scalp care, but has been inspired by our episode to amp up her routine. That said, she currently uses Briogeo Scalp Revival Charcoal + Coconut Oil Micro-Exfoliating Shampoo to help slough away product buildup, as well as dpHue Apple Cider Vinegar Hair Rinse. Michelle says the blend provides a far more elegant way of benefitting from the clarifying effects of ACV than, say, pouring the straight stuff on your head. (Which we may or may not have asked her to do during episode seven…)

Jenny’s Current Favorites

Jenny has tried all kinds of scalp exfoliators, but she’s stuck with TPH by Taraji Master Cleanse Scalp Treatment Wash because unlike other formulas, it’s not a grainy scrub which she often finds tricky to fully rinse out of her hair. Instead, it has tea tree and eucalyptus oils, which help get rid of gunk far more gently. Plus, the formula is dispensed through a pronged applicator, which enables you to “really get it down to your scalp,” says Jenny.

Briogeo

Briogeo Scalp Revival Charcoal + Coconut Oil Micro-Exfoliating Shampoo

dpHue

dpHUE Apple Cider Vinegar Hair Rinse

TPH by Taraji

TPH by Taraji Master Cleanse Scalp Treatment Wash

The Bottom Line

To put it simply, scalp care is skin care — so pay some extra attention to the top of your head.


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