What is sebum?

Buying decisions can be easy, spontaneous, driven by habit - but they can also be quite a challenge when we have no clearly defined preferences or, worse still, no certainty about what we actually need. We then have to weigh up a whole range of factors - and when it comes to choosing cosmetics, the most important of them (alongside price) turns out to be what the manufacturer tells us about the product.

Everything we need to know about a product should be in its description - especially the claims about the effects we can expect from it. One example of such a claim (to use the industry jargon) is the phrase "regulates sebum secretion". You are certainly familiar with it, but have you ever stopped to think about what it means? What exactly is sebum, how is it secreted and why might we feel tempted by the prospect of regulating it? Allow us to explain a thing or two ;).

Sebum - what exactly is it?

If we reach for the official definition, sebum is the natural lubricant (or, to put it simply, moisturiser) of the skin of almost all mammal species. Another name for it is skin oil, or sebaceous matter - because it is the secretion of the sebaceous glands located in the middle layer of our skin.

Every sebaceous gland is built and programmed in such a way that for about a week it produces lipids inside itself, and then disintegrates, passing its product on to the neighbouring hair follicle, to which it is connected by a special duct. From that moment on, the hair growing out of the follicle transports the sebum upwards, carrying it to the surface of the skin. The amount of sebum that appears on our skin depends on how numerous and how large our sebaceous glands are - some sources say that on average around 1-2 grams of it is secreted per day. When we take a closer look at it, we can say that sebum is a liquid, oily, slightly sticky and odourless substance with a faintly yellowish tint. At this stage it does not sound unfriendly at all, does it? And quite rightly so!

Sebum is an inseparable, essential element in the process of keeping our skin healthy and in good condition. Just look at the list of its functions:

- it forms a versatile protective layer - thanks to its slightly acidic pH it works as an antibacterial, antifungal and therefore anti-inflammatory agent, stopping pathogens from entering our body through the skin,
- it limits the evaporation of water (the so-called transepidermal water loss), helping to maintain proper hydration and, as a result, the elasticity and softness of the skin,
- it transports fat-soluble antioxidants (such as vitamin E) to the surface of the skin, supporting the skin's protection against the harmful effects of UV radiation and free radicals.
Fun fact:
Sebum is a complex mixture of lipid substances, and its exact percentage composition can differ depending on age, for example. It contains, among other things, glycerides, fatty acids, cholesterol and its esters, but the most characteristic and at the same time unique components of sebum are squalene and specific wax esters - these lipids do not occur anywhere else in the body!

As you can see, sebum is an extremely beneficial product of a natural process, one of the many expressions of our body's evolutionary wisdom. Unfortunately, at a certain point in human development the "shine" of skin covered with sebum came to be considered unattractive... In this respect an analogy between sebum and sweat comes to mind - some of us try hard to get rid of both, working against ourselves, when in fact we ought to care about protecting our skin and preventing our body from overheating. So let us not demonise either process in the name of a culturally imposed aesthetic.

Depending on the area of skin, every square centimetre of it may contain as many as 900 sebaceous glands. We will find the most of them on the face, the chest, the middle part of the back and in those places where our hair grows most abundantly - on the scalp or the genitals. What may come as a surprise, a high density of sebaceous glands is also found in... the ear canal! We have very few of them on the hands and feet, on the other hand - the palms and the soles have none at all, but they make up for it with the highest density of sweat glands :).

The key word: balance

"Too much of anything is bad for you" - as our parents and grandparents used to say. In the case of sebum, however, we can safely add that too little is not the best either. If our sebaceous glands are characterised by overproduction or insufficient production of sebum, we may struggle with all sorts of skin problems - oily skin (seborrhoea) or acne on the one hand, and constant irritation or itching on the other. A shortage of skin oil makes the skin dry and often excessively flaky.

Oily and combination skin

We speak of oily skin when the sebaceous glands located on the face, as well as in the central part of the chest and back, show increased activity - in these areas they are not only more numerous, but also larger than in other parts of the skin. The characteristic shine of skin covered with sebum often goes hand in hand with more visible pores. Combination skin, in turn, is characterised by an excess of sebum on the nose, chin and forehead (the so-called T-zone) alongside a tendency towards dryness and sensitivity on the cheeks.

But what determines how much sebum our sebaceous glands secrete? Their size and number are genetically determined, but their actual activity over the course of our lives depends on our genes only in part. Day to day, sebum production - and any disturbances of it, whether towards excess or deficiency - is governed above all by our hormonal balance, with inappropriate skincare possibly playing its part too.

Sebum and hormones - the bane of every teenager ;)

We assume that most of you have already lived through that memorable period called puberty. Some of you may be going through it right now, or accompanying your own offspring as they wrestle with it in all its glory. Whichever group we currently belong to, chances are a shiver runs down our spine at the mere sound of words like acne, greasiness or hormones... ;). In this exceptional period of life it is precisely this "trinity" that seems to be the source of all our skin problems - the cause-and-effect chain looks like this: hormones, wildly active at this time, get sebaceous gland production going in earnest, and excessively secreted sebum is one of the main causes of acne lesions. Let us take a look at it step by step.

Sebum secretion

The secretion of sebum is controlled by sex hormones from the androgen group, colloquially called male sex hormones - although they circulate in our bodies regardless of sex, produced by the gonads (ovaries or testes) and the adrenal glands. In the male body their concentration is usually higher, which is why both adolescent boys and adult men naturally have skin somewhat more prone to excessive greasiness than their female peers. The relationship is very simple - the higher the concentration of androgens, the more the sebaceous glands are spurred into action. They react with particular enthusiasm and energy to the most active form of testosterone, known as DHT. In childhood our sebaceous glands remain relatively shrunken and inactive - you could say that from the moment they form in foetal life and fulfil their task of protecting delicate skin in infancy, they wait lazily for us to become teenagers. When we start going through puberty, DHT activity rises sharply, stimulating sebum production - which can increase by as much as 500 percent! At this point you may kindly thank DHT for teenage acne, greasy hair and other dubious pleasures of those years ;).

The peak of sebaceous gland activity falls roughly between the ages of 15 and 35, though it may begin earlier - and it may also gradually slow down once adulthood is reached. The amount of sebum secreted steadily decreases with age, accompanied by changes in its composition and inescapable differences in the condition of the skin.

Fun fact:
Do you know squalane from sugar cane? It is the plant-based counterpart of squalene, that unique component of sebum which gives the skin softness and elasticity and protects it from water loss. When we lack squalene (and not only because of age), the skin loses its firmness, becomes dried out and dull. We do have good news though: Ministerstwo's sugar cane squalane makes a perfect substitute! :)

To be a woman, to be a woman...

Scientific research shows that sebum production is also influenced by another sex hormone, this time a female one - progesterone. When its level in the body rises, the amount of sebum secreted rises along with it, something women may notice particularly in the so-called luteal phase of the menstrual cycle, that is roughly a week before bleeding starts and during the period itself. In that time it is worth taking particular care to keep your skincare light and non-burdening :). Interestingly, changes in the amount of sebum secreted across the phases of the cycle were not observed in women who naturally produce little of it - only in those with combination and oily skin. In this second group it is often accompanied by the appearance of new, temporary acne lesions or a flare-up of existing acne. Acne lesions linked to the menstrual cycle usually appear along the jawline and on the chin, often in the form of painful, somewhat hard "lumps" located deep beneath the skin.

Fun fact:
Oral combined hormonal contraception is sometimes used as an anti-seborrhoeic and anti-acne medication - by blocking ovulation, it stops the ovaries from producing androgens, which in a naturally running cycle stimulate sebum production. For the same reason, taking this form of contraception may in turn contribute to increased dryness and sensitivity of the skin in people whose sebaceous glands naturally produce only a small amount of sebum.

The enemy under the microscope

We have already established that one of the factors behind the appearance of our skin adversaries is excessively secreted sebum. Time to find out how this happens and to get to know the various types of acne lesions a little better.

First up, let us put comedones under the microscope, and more precisely their two types:

• closed comedones, that is whitish bumps under the skin - they form when impurities accumulate in the opening of the hair follicle and close it off completely,
• open comedones, sometimes called blackheads - they form when the opening of the hair duct is not completely closed, so the accumulated impurities oxidise and harden, creating "black dots".

Fun fact:
Every one of us has so-called sebaceous filaments in our hair follicles, which can look like tiny comedones - in people with combination and oily skin both become particularly visible on the nose and cheeks. Sebaceous filaments do not block the pores, however; they play an important role in transporting sebum to the surface of the skin, which is why you should not only refrain from trying to remove them, but also not count on them staying away for long once removed :).

Comedones are not inflammatory lesions, but unfortunately they have the potential to turn into them. In such a closed, oxygen-free environment, Cutibacterium acnes bacteria (harmless to our skin under normal conditions) can develop, triggering inflammation and turning comedones into acne lesions - pustules, papules or cysts. At this point allow us to point out that we can unwittingly assist the process described above if we have a tendency to fiddle with comedones with restless fingers ;). The impurities that gather in our pores, leading to the formation of comedones, are a combination of sebum produced in excess, dead skin cells, and things like dust or cosmetic residue. In the case of the latter we often speak of a tendency to "clog", that is comedogenicity (from the English comedone). Comedogenicity means that a given substance blocks the openings of the hair follicles and, with long-term use, leads to the formation of comedones (this usually happens after 2-3 weeks!).

Fun fact:
The comedogenic potential of cosmetic ingredients is determined for their 100% concentration, that is for the substance in its pure form. In the case of complex cosmetic products, whose formula consists of many ingredients in various percentage concentrations, we cannot clearly predict whether a given cosmetic will "clog" our pores on the basis of the presence of a potentially comedogenic ingredient alone.

Fun fact:
When we talk about clogging, we sometimes also mean another property of a substance, known as acnegenicity (from acne). Acnegenic ingredients can irritate the hair follicle, thereby triggering inflammation and the formation of a pustule. This happens much faster, however, than the clogging of pores by comedogenic substances - usually between 48 and 72 hours after the product is applied.

Keeping secretion a secret ;)

Time for the key question - how can we regulate the secretion of sebum? When our skin goes greasy, our first thought may be to stubbornly degrease it, cleanse it, dry it out... absolutely not the way to go. If we remove the lipids from the surface of our skin, for instance through intensive scrubbing or wiping with an alcohol-based toner, the initial effect of a matte appearance may be satisfying. But let us imagine what comes next: the skin loses its protective layer, becomes sensitive and vulnerable to environmental factors. It can defend itself in only one way - by alerting the sebaceous glands and stimulating sebum production! Repeating this pattern in our daily skincare traps us in a vicious circle of excessive greasiness. Using mattifying make-up is a purely superficial solution; it does not address the problem at its source and does not translate into long-term change. If we want a lasting improvement in the condition of our skin, it is best for matte make-up to go hand in hand with well-chosen skincare. Let us take care of a healthy balance between cleansing and exfoliating the skin, normalising sebum secretion, and moisturising and regenerating. It is a myth that oily skin must not be moisturised so as not to make the greasiness worse. Let us think about it the other way round - if we help the skin maintain proper hydration, our sebaceous glands will not have to work nearly as hard!

An important factor - skin hydration

Every skin type needs hydration - but if our skin is characterised by overproduction of sebum, the most important thing is to deliver it without weighing the skin down. It is worth going for products rich in hydrophilic ingredients that bind water in the epidermis, but also containing light emollients (with the emphasis on light!) that will limit its evaporation. Do you remember squalane? :) It is one of our favourite ingredients, adored as a solo player but also unfailing in multi-ingredient cosmetic formulas in this category. When creating Ministerstwo products, whenever we need a light formula and a non-greasy finish on the skin, we reach for sugar cane fractions (in INCI you will find them under the names Squalane and Hydrogenated Farnesene), as well as the equally light tripelargonin - obtained from milk thistle seeds. Squalane itself takes the form of an exceptionally light, odourless and beautifully absorbing oil that works in the care of every skin type. It moisturises, protects and nourishes the skin wonderfully without leaving a feeling of heaviness, which is extremely welcome for people with oily and combination skin. It brightens the skin and gives it radiance, improving the look of dull, tired skin, and it also reduces the visibility of wrinkles and restores the skin's elasticity and firmness.

Hydrolates can be an excellent element in the care of combination, oily and acne-prone skin - they effectively raise the skin's hydration level, and thanks to their watery form they do not weigh it down. We especially recommend paying attention to those hydrolates whose antibacterial action has been proven in instrumental testing, and whose sebum-regulating, grease-reducing and shine-preventing properties have been confirmed by users in application tests. In alphabetical order, ours are: bay laurel, lavender, mint, witch hazel, rosemary and pine hydrolate.

The star of our range for skin prone to greasiness, however, is this one - the H2O Hydromineral face cream. This light cream with a strongly moisturising action leaves no greasy layer on the skin, does not clog pores and, most importantly, its regular use reduces the amount of sebum secreted by the skin by as much as 12% - the drop in sebum production is visible after just 2 weeks of regular use! It owes this effect to, among other things, its niacinamide content - an exceptionally valuable ingredient in the care of combination, oily and problem skin, with regulating and antioxidant properties which also lightens fresh, red post-inflammatory marks.

Coming back to squalane for a second, we have to mention that it too has sebum-regulating properties - it reduces sebum production by as much as 16%, prevents the skin from shining and, thanks to its soothing and calming properties, reduces the number and visibility of imperfections. A wonder, a treat and squalane ;).

Excess sebum and oils in skincare - how to approach it?

Having overactive sebaceous glands does not disqualify you from using oil-based products in your skincare, including pure, one hundred percent plant oils. All you need is to stick to two key rules:

• choose light oils and oil blends, ideally with low comedogenicity (you will easily find information on this online by typing "comedogenicity scale" into a search engine - what interests us above all are oils that score 0 or 1),
• place particular emphasis in your routine on thorough but gentle cleansing, preferably in two stages, so that residues of oil-based cosmetics do not linger on the surface of the skin.

Allow us to draw your attention to a few Ministerstwo products that fit these rules perfectly. In the first category, raspberry seed oil takes the lead - it is characterised not only by a light consistency, a matte, almost dry finish on the skin and low comedogenicity (0-1), but on top of that it showed in instrumental testing an effect reducing sebum secretion by 7.6% after 4 weeks of regular use. The ideal candidate to replace a serum or a cream, especially for skincare minimalists and naturalists! You may also look kindly upon hazelnut oil, which alongside its low comedogenicity (1) is credited with astringent properties that reduce the visibility of pores.

The second category is where our duo of cleansing products gets to shine - the Rose-Raspberry hydrophilic cleansing oil (nothing washes off fats as well as other fats!) and the Apricot face wash foam. Thorough removal of impurities without leaving a greasy layer on the skin, but also without drying it out? Ticked off! Studies confirm it unequivocally - regular use of the foam reduces sebum secretion by 20% (!), eliminating shine and leaving the skin matte.

Extras make the difference - clay masks

If you struggle with imperfections or seborrhoea, it is worth including a clay mask in your routine as well, done 1-2 times a week as an extra step between washing your face and applying moisturising products. Clays have fantastic sebum-absorbing, cleansing, pore-tightening and mattifying properties - in the care of excessively greasy skin, green clay works best, mixed with a chosen antibacterial hydrolate and a touch of regulating raspberry seed oil.

If, on the other hand, what bothers you is excessive greasiness of the skin on your body, we suggest washing daily with rosemary soap, which combines the properties of blue clay and antibacterial rosemary oil, with the occasional assistance of the anti-inflammatory and micro-exfoliating Charcoal soap used once a week. It will also do no harm to wipe the areas of the body where imperfections appear with a cotton pad soaked in hydrolate, or even to add a portion of clay to your bath - after all, there is no need to limit their valuable action to facial care only :).

Sebum - a natural hair conditioner

As we mentioned earlier, the scalp is one of those areas with the greatest number of sebaceous glands and at the same time the biggest opportunity for our skin oil to show what it can do - here it has to take care not only of the skin itself, but of the hairstyle too! By coating the hair, sebum gives it softness and protects it from damage. In the acidic environment of sebum the hair cuticles arrange themselves in an even, tight pattern (you can picture tiles on a roof :)), giving the hair smoothness and shine - without it, hair can become prone to breakage and tangling, dull and brittle. Of course, as with facial skin, balance is what matters most - our hair needs sebum, but in healthy moderation, which is worth looking after with the right scalp care. What is worth paying particular attention to if you are struggling with excessively greasy hair?

The basis is washing that is not only regular but also correct - we absolutely do not leave the scalp to fend for itself, assuming that if we get it used to infrequent hair washing, the skin will eventually regulate itself. Sebum is an excellent food source for the microorganisms living on its surface! The triglycerides it contains are gradually broken down by bacteria and yeasts into fatty acids, which in turn can be irritating, act as a stimulating factor for the sebaceous glands and cause unpleasant itching. That is a straight road to dandruff or seborrhoeic dermatitis. For this reason it is worth reaching for shampoo regularly, every 1-3 days, even if your hair still looks fine after that time. How we use that shampoo is extremely important - believe us, this is by no means common knowledge!

• Every shampoo is best lathered first (in your hands or in any small container) with a little water, and the resulting foam applied to the head.
• People customarily say "shampoo for hair..." (for greasy hair, for instance), but shampoo is used above all to wash the scalp, massaging it thoroughly with your fingertips and paying particular attention to the hairline around the face, or the often overlooked areas behind the ears and just above the nape.
• No worries - the foam running down will easily wash the impurities off the lengths of your hair, there is no need to scrub and tangle them additionally :).
• It is best to leave the foam on the skin for a few minutes so that the cleansing substances have time to bind the sebum.
• The whole process, especially in the case of an excessively greasy scalp, is worth repeating twice. Some people compare it to washing a greasy frying pan - first the preliminary wash, then the proper one ;).
• After washing, squeeze the water out of your hair - do not rub it with a towel so as not to break it, but also do not keep it wrapped up in a turban. Such a warm and damp environment favours the growth of microorganisms, contributing not only to increased sebum production but also to the development of skin conditions (dandruff, for instance).

To anyone struggling with hair that gets greasy too quickly, we recommend reaching for the Green Tea shampoo bar in daily care; it improves the condition of the scalp, which becomes cleaner and free of dandruff, while the hair stays fresh for longer. Here too you can benefit from the properties of the organic hydrolates from Ministerstwo Dobrego Mydła, spraying them onto the scalp and gently massaging them in as a treatment lotion. Rosemary is particularly good at soothing irritation and scalp problems :). If, on the other hand, you use conditioners or oils in your hair care, we recommend applying these products to the lengths of the hair only - people customarily talk about applying them "from the ear down", so as not to weigh the scalp down.