Scalp sebum is common in people with hair loss.
The sebum is a buildup of oils, dead skin cells, and waste products excreted through the skin.
It can also be caused by hair care products such as shampoos, conditioners, dyes, masks, and other topical products.
Scalp sebum doesn’t necessarily cause hair loss, but if it is excessive then it can lead to issues with the overall health of your hair.
Taking the time to clean away the buildup and prevent it from coming back as regularly is a good idea for the general health of your hair and in some cases may help stop further loss of hair.
Scalp sebum may trap DHT against the scalp, making hair follicle miniaturization more likely. It can also stop topical hair growth products such as minoxidil from being so effective because they don’t come into contact with the scalp as much.
In this article you’ll learn what causes the sebum to be created and build up in the first place, and learn more about how it can affect the hair follicles and prevent them from growing in a healthy way.
You’ll then learn the most effective ways to cleanse the scalp and remove the buildup so you can start fresh with a revitalized scalp.
What Is Sebum?
Sebum is a complex amalgamation of lipids, or oils, produced by the sebaceous glands of your scalp.
Although sebaceous glands are found throughout the body — except for the palms or your hands and the soles of your feet — the ones that are associated with your hair follicles are a different type than those on the rest of your body.
The process by which sebaceous glands produce sebum is called the holocrine process (1).
During this process, cells inside the sebaceous glands become full of sebum, rupture, and release the sebum along with the remains of the cells into the duct of the hair follicle.
Sebum has several functions in humans, among them (2):
- Antimicrobial activity
- Providing fat-soluble antioxidants to the surface of the skin
- Anti- and pro-inflammatory activity, depending on specific lipids
Human sebum is mainly composed of wax, squalene, free cholesterol, esters of glycerol, and fatty acids (3).
The most dominant component is fatty acids and triglycerides, which make up more than half of the substance (4).
Next is wax esters and squalene, with cholesterol being the least prevalent. The least abundant lipid in sebum is cholesterol (5).
Squalene and wax esters are unique to sebum and not found anywhere else in the body (6).
Although excess sebum can be problematic, sebum itself is important for contributing to the scalp’s proper pH and moisturizing your hair and scalp (7).
It is only when too much sebum is produced or when it is allowed to build up on the scalp that it can be detrimental to hair growth, as we’ll explain later.
Why Does Sebum Build Up on Your Scalp?
The sebum-producing sebaceous glands are located at the base of the hair follicles in pilosebaceous units (8).
This big word simply means the glands are paired with both the hair follicle and the arrector pili muscle into one coordinated entity. The arrector pili is the tiny muscle that allows your skin to contract into a “goosebump.”
Because the sebaceous gland is attached so closely to your hair’s follicle, when excess sebum is produced quickly it can’t escape the follicle and it coalesces into a plug or ball, forming a build-up.
This build-up can occur for several reasons, which we’ll explore now.
Shampooing your hair too often because it is “greasy” can contribute to overproduction of sebum (9).
This is because when you wash daily, you can dry out the hair follicles and scalp. Your body is smart, and it always seeks balance.
To compensate for the dryness caused by constant exposure to hot water and shampoos, your sebaceous glands increase production of oil, causing an even oilier scalp (10).
This, of course, can lead to even more shampooing, which completes the circle and keeps your production of sebum high.
Your environment can play a big part in the quantity, and makeup, of the sebum produced.
Environmental factors that affect sebum production include both temperature changes and environmental pollutants like cigarette smoke and poor air quality (11, 12).
If you can, it’s best to work and live in an area with good air quality and avoid exposure to airborne chemicals.
Sebum can be increased during summers or in hot environments, as the sebaceous glands are part of our body’s cooling mechanism and naturally produce a “sweat sheet” when we are exposed to high temperatures.
However, in cold environments, the nature of the sebum changes. While we may not produce as much, it is thicker to act as a water repellent (13).
Again, the natural production of sebum is an essential part of your body’s functioning. It is only when it is overproduced or changed in some way, that it becomes a problem.
Both men and women produce testosterone, a sex hormone necessary for proper functioning in both sexes.
When testosterone is secreted by the body and picked up by the sebaceous gland, the enzyme 5-alpha reductase (5AR) immediately begins to convert it into di-hydrotestosterone (DHT). DHT then causes the sebaceous glands to begin producing sebum (14).
The enzyme 5AR, being sensitive to levels of circulating hormones, works harder when testosterone rises, as during puberty and this increases sebum production.
While hormones alone are not the cause of excess sebum, research shows it’s possible that 5AR becomes more sensitive to testosterone so even in individuals with low testosterone, there may be increased sebum production (15).
Another cause of increased sebum production is Androgenetic Alopecia (AGA), the most common form of hair loss.
In AGA, hair follicles become sensitive to DHT, a hormone produced naturally in the body.
This sensitivity causes a process called hair follicle miniaturization, during which time hair transitions from strong, terminal hairs to vellus, or thin, fine, “baby” hairs, to total baldness (16).
This miniaturization, in turn, causes the sebaceous glands that lie in conjunction with the hair follicles to overgrow and produce excess sebum (17, 18).
The excess sebum then proceeds to clog the follicles, contributing to inflammation and irritation and causing miniaturization to proceed more rapidly (19).
Our modern diet is laden with processed, high-glycemic, chemically-infused foods.
In addition, we prepared many of our standard meals in ways that are unhealthy — by deep-frying, drenching them in fats and oils, and overcooking.
In this way, we contribute to nutrient deficiencies and inflammatory processes that can directly affect our hair (20, 21).
How Can Sebum Build-Up Affect Hair Follicles?
Now that we’ve looked at the many catalysts that can contribute to the build up of sebum on your scalp, let’s explore how this build-up can affect the health of your hair follicles and contribute to hair loss.
The most critical mechanism by which sebum affects hair follicles is to clog the follicle base.
Not only does this cause inflammation and irritation, but it concentrates the amount of DHT near the bulb of the follicle (22).
As mentioned, DHT is considered a leading cause of hair loss, and in the case of excess sebum production, the sebum is keeping it from being removed from your scalp.
7 Ways to Treat and Prevent Sebum Build-Up
There are many ways that you can prevent excess sebum from affecting the health of your hair follicles.
In the following paragraphs, we’re going to explore many of them, from topical treatments to lifestyle changes.
Niacinamide is the active form of the vitamin B3. It’s been widely used to prevent pellagra and is also useful in managing arthritis and Type I diabetes of the early-onset variety (23).
Niacinamide has also been studied as an anti-aging component and is included in many cosmetic preparations (24).
When it comes to reducing sebum production, niacinamide has a good track record.
Study: Niacinamide Reduces Sebum Production
One study focused on the use of a 2 percent topical niacinamide solution to reduce facial sebum production in both Japanese and Caucasian subjects (25).
One hundred Japanese subjects took part in a placebo-controlled, double-blind comparison.
Fifty subjects used a moisturizer containing 2% niacinamide for four weeks while the other 50 subjects used a placebo. The sebum excretion rate (SER)was measured at study onset, then weeks 2 and 4.
For contrast, 30 Caucasian participants took part in a six-week split-face randomized with SER and casual sebum levels (CSL) measured at study onset and weeks 3 and 6.
The Japanese group using the niacinamide moisturizer had significantly lower SER at weeks 2 and 4.
In the Caucasian group, CSL was significantly reduced after 6 weeks, but SER reduction remained insignificant.
This meant that both sebum excretion rates and casual sebum levels were significantly reduced after 6 weeks of treatment, dependent on ethnicity.
Study: Topical Niacin Increases Hair Fullness
A six-month pilot study that examined topical niacin derivatives for female pattern baldness showed a statistically significant increase in hair fullness in sixty female study participants on blinded 35-mm photographic analysis (26).
The subjects presented with Ludwig types I-III female pattern hair loss and they were evaluated in a placebo-controlled, double-blinded study.
Although there was no discussion of the mechanism by which hair fullness was achieved in this study (i.e., through sebum reduction or removal of some other causal factor), it is interesting that increased hair growth was observed.
The researchers state:
“Long-term topical application of nicotinic acid derivatives offers promise for providing benefit in female alopecia and warrants further study”
Because niacin and niacinamide are often used interchangeably, these results could point to either one being an effective adjunct to your sebum control program (27).
2. Green Tea
Tea from the leaves of the Camilla sinensis plant has long been considered a source of health-giving micronutrients and a natural curative for many disorders (23).
It is also a helpful adjunct to control sebum production. A small study testing the efficacy of a 3 percent green tea extract combined with a proprietary emulsifier on 10 male volunteers found that long-term application resulted in a significant reduction in sebum production on facial skin (p < 0.5%).
Other studies on the interaction of topical green tea with sebum production produced promising results, but larger and higher quality studies are needed (24, 25).
L-carnitine is an amino acid that helps with metabolism and is naturally produced in your body. Specifically, it helps to break down fatty acids.
Study: L-carnitine is Bio-Available and Reduces Sebum
One study showed that 2% L-carnitine, applied topically, resulted in significant sebum reduction in both in vivo and in vitro experiments (26).
The in vitro studies used the human sebaceous cell line SZ95 and a cosmetic formulation comprised of radioactively labeled L-carnitine.
To determine the in vivo effects, a three-week, randomized, vehicle-controlled, study used a cosmetic formulation containing 2% L-carnitine.
At study end, sebum production was measured using the lipid-absorbent Sebutape(®).
The SZ95 cells treated with 0.5% or 1% L-carnitine demonstrated a significant increase in β-oxidation that was dependent on concentration in comparison with control cells.
Additionally, intracellular lipid concentrations also decreased significantly manner related to dose as compared with control cells that were not treated with L-carnitine.
Finally, participants in the topical in vivo application saw significantly decreased sebum secretion.
“Topically applied L-carnitine is bioavailable and leads to a significant sebum reduction in vivo”
However, further studies evaluating the sebosuppressive properties of L-carnitine are necessary to confirm these results, as studies have been small and sporadic.
4. Spironolactone, Especially for Women
A common hypertensive medication and diuretic, spironolactone has been proven to reduce sebum production (27).
Study: Spironolactone Reduces Sebum Production, Especially in Women
In a study involving 26 male and female subjects with severe acne were evaluated in a double-blind study of three months duration.
During this time, subjects were given 50-200 mg per day of spironolactone.
Twenty-six patients completed the study and spironolactone was found to reduce sebum excretion in all female subjects, although researchers did not comment on the results for the male subjects.
The best results were seen with spironolactone doses of 150-200 mg.
In addition, spironolactone seems to inhibit DHT production and blocks testosterone and DHT from attaching to sebocytes.
This not only reduces sebum production, but has been modestly effective in treating female androgenetic alopecia (36, 37).
5. Choose a Natural Shampoo
Many hair care products are full of emulsifiers, waxes, and chemicals that may clog the pores of your scalp and contribute to sebum build-up.
One way to avoid this is to “shampoo” your hair with a rinse of apple cider vinegar and water, making sure to rub it into the skin of your scalp.
Apple cider vinegar has anti-inflammatory properties and it’s a mild acid that can remove hair product film and sweat as well as balance the pH of your scalp (28).
If you want a more traditional approach to hair cleansing, try a caffeine-infused shampoo prepared with natural ingredients.
Caffeine has hair-growth stimulating properties and as long as the shampoo is made with gentle, natural ingredients it should help to maintain your scalp’s health so long as you don’t overuse it.
6. Shampoo Less Often
As we mentioned, many people shampoo their hair too often, initiating a vicious cycle of sebum production.
Instead of daily shampooing, aim for every other day, and less if you can. Often one to two times per week is plenty.
Of course, if you exercise to the point of heavy sweating, you may need to shampoo more often to remove excess dirt and sweat.
7. Change Your Diet
This is a big step, but it’s also one of the most powerful things you can do for the health of your hair.
As we mentioned, nutritional deficiencies and a lifetime of eating processed, unhealthy foods can take a toll on your hair follicles.
Your skin is your body’s largest organ, and it’s the one that helps the body rid itself of toxins through sweat and other secretions (29, 30).
And yet we eat a diet high in fats and sugars that is shown to correlate with low immunity, skin dysfunction, and with hair loss (40, 41).
But there’s hope.
Research shows that following a low-glycemic diet can have profound effects on skin health and directly affect sebum production (42).
The subject of diet is too broad to discuss in full in this article, but for some quick tips, consider the following:
- Reduce consumption of fatty meats and processed foods
- Eliminate vegetable oils and fried foods
- Increase your consumption of raw or lightly cooked vegetables
- Increase your consumption of fruit
- Use fats from coconuts, avocados, and nut and seed oils to cook
Any improvements that you make over the standard Western diet will help to improve your health and the health of your hair.
Sebum build-up can contribute to lackluster hair, and leave your hair greasy and hard to manage.
But if left untreated, the build up of sebum can also contribute to a much larger problem — hair thinning.
Fortunately, there are easy solutions to both treating — and preventing — the problem of excess sebum that will help you maintain the health of your hair follicles.
And you don’t have to resort to expensive products to manage your hair’s health when it comes to sebum.
With some simple changes in hygiene, diet, and lifestyle, you can be well on your way to controlling excess sebum and helping your hair follicles be as strong as they can be.