A healthy scalp is the foundation for strong, shiny hair. Yet many people experience complaints such as dryness, itching, flaking, excess sebum production, or hair breakage without fully understanding what causes them. Hair and scalp are part of the same biological system: the hair follicle. Anyone who understands that system can make more targeted choices about what supports their hair and scalp. In this guide, we discuss the key processes, the causes of common complaints, and how gentle, natural care can help keep everything in balance.
1. Structure of hair and scalp
Hair grows from the hair follicle, a complex mini-organ anchored deep in the dermis. Each follicle produces one hair shaft and works closely with the adjacent sebaceous gland. The sebaceous gland secretes sebum, which is transported via the follicle to the hair surface and the scalp. This is also why the health of the scalp and the condition of the hair are so closely linked: they share the same system.
The hair shaft itself consists of three layers. The inner core is called the medulla, around it lies the cortex, which determines the strength and color of the hair, and the outer layer is the cuticle: overlapping, roof-tile-like hair scales that protect the hair shaft. An intact cuticle provides shine and flexibility. When the cuticle is damaged by heat, UV, chemical treatments, or mechanical friction, the hair becomes more porous, drier, and more brittle.
The scalp has more sebaceous glands per square centimeter than almost any other part of the body. That makes the scalp more sensitive to disruptions in the sebum balance than, for example, the arm or back. At the same time, the presence of sebum naturally protects the scalp and hair.
2. The scalp barrier
The scalp barrier works in the same way as the skin barrier on the face: a combination of skin cells, lipids, and microorganisms forms a protective layer that limits moisture loss, keeps out external irritants, and protects the structures beneath the skin. When this barrier is intact, the scalp maintains a good moisture balance, is less sensitive to irritants, and produces sebum at a healthy rate.
Scalp barrier disruption happens faster than people think. Shampoos with harsh sulfates, water that is too hot, washing too often, or excessive use of styling products can all contribute to a weakened barrier function. The symptoms that follow, such as itching, flaking, dryness, or even excess sebum production as a compensatory mechanism, are signals that the scalp has lost its balance.
An itchy or flaky scalp does not necessarily mean you need to wash more or more often. Often the opposite is true: less frequent, gentler cleansing gives the scalp barrier room to recover.
The link between the scalp barrier and hair condition is direct. A healthy barrier supports the hair follicle, which contributes to regular, strong hair growth. A chronically disrupted barrier can have the opposite effect.
3. Sebum production and hair condition
Sebum has a bad reputation, but in the right amount it is essential for both the scalp and the hair. It is the most natural conditioner there is: sebum spreads along the hair shaft to the hair tips and gives hair its naturally shiny, supple character. People with very short hair or a shaved head notice this clearly: the skin produces sebum, but there is no hair to absorb it, which leads to a greasy feeling on the scalp.
Too much sebum
Excess sebum production leads to an oily scalp, limp hair, and faster buildup of dust and product residue. The tendency is then to wash more often, but that can set off a vicious cycle: more frequent washing stimulates the sebaceous glands again, making the scalp feel oily faster. Gradually extending the time between washes, combined with gentle products, helps normalize sebum production over time.
Too little sebum
A shortage of sebum shows up as a dry, tight scalp, flaking without greasiness, and brittle, dull hair. This can result from harsh cleansing, climatic conditions such as cold dry air, or hormonal changes. In this case, gentle plant oils can help support the scalp's lipid layer.
4. The scalp microbiome
The scalp is home to its own ecosystem of bacteria, yeasts, and other microorganisms. This microbiome plays an active role in protecting the scalp, regulating barrier function, and keeping sebum production in balance. One of the best-known microorganisms on the scalp is the yeast Malassezia, which is naturally present but, when overgrown, is associated with flaking and sensitivity.
The scalp microbiome is sensitive to outside disruption. Shampoos with strong antimicrobial ingredients, washing too often, occlusive styling products, and even changes in climate can affect microbiome balance. As with the skin on the face, the fewer harsh substances applied to the scalp, the more stable the microbiome generally remains.
Gentle cleansing, a moderate washing schedule, and restraint with heavy styling products are the most effective ways to support the scalp microbiome. You can read more about the role of the microbiome in our blog on itchy scalp and a gentle routine. For the difference between dandruff and a sensitive scalp, and how Malassezia plays a role in it, read our blog on dandruff and sensitive scalp.
5. Dry scalp versus dry hair
Dry scalp and dry hair are often mentioned together, but they are two fundamentally different phenomena with different causes and solutions. They can occur at the same time, but they do not have to.
Dry scalp
A dry scalp results from a lack of lipids in the skin barrier. The scalp feels tight, there is flaking that is loose and dry, and there may be itching or sensitivity. Common causes include harsh cleansing, hard water, low humidity, and hormonal fluctuations. Treatment focuses on restoring the barrier function: gentler cleansing, less frequent washing, and possibly plant oil as a scalp treatment. You can read more about this in our blog on the difference between dry scalp and flakes.
Dry hair
Dry hair is damage to the cuticle of the hair shaft. The hair scales are damaged or lifted, allowing moisture to escape from the hair shaft and external substances to penetrate more easily. Dry hair feels rough, is difficult to detangle, lacks shine, and is prone to static electricity. Causes include heat styling, UV exposure, chemical treatments such as coloring or bleaching, and mechanical stress from brushing too hard or towel rubbing.
So the approach is different: with a dry scalp, you restore the skin's lipid layer; with dry hair, you protect and repair the hair shaft cuticle. Oils play a role in both, but the application differs.
| Dry scalp | Dry hair | |
|---|---|---|
| Cause | Lipid deficiency in the skin barrier | Damaged cuticle of the hair shaft |
| Symptoms | Flaking, itching, tight scalp | Rough, dull, brittle hair, difficult to detangle |
| Causes | Harsh cleansing, hard water, low humidity | Heat, UV, chemical treatments, friction |
| Approach | Gentler cleansing, oil on the scalp | Protect the cuticle, oil on the hair shaft |
6. Hair porosity and oil absorption
Hair porosity determines how easily the hair shaft absorbs and retains moisture, and is therefore one of the most important factors in choosing the right oil for your hair. Low porosity calls for lightweight oils that do not sit on the surface, while high porosity tolerates richer oils that weigh down the cuticle and limit moisture loss. Which oil suits which porosity, how to recognize porosity, and why one oil weighs down your hair while another works well are explained in detail in our blog about hair porosity and oils.
7. Product build-up and mechanical damage
Build-up is the accumulation of product residue on the hair shaft and scalp. Silicones, waxes, and heavy conditioners build up with each wash, leading to dull, heavy hair and a tight feeling on the scalp. Hard water makes this worse because limescale residue disrupts the cuticle. You can read how to recognize build-up, what hard water has to do with it, and how to address it gently in our blog on product build-up and hard water.
Mechanical damage
In addition to chemical and thermal stress, mechanical stress is an underestimated source of hair damage. Hard brushes, rough towel drying, tight hairstyles, and sleeping on cotton pillowcases create friction that damages the cuticle. Soft materials, gently detangling wet hair, and looser hairstyles are simple but effective adjustments.
Wet hair is vulnerable: the hair shaft is swollen and the cuticle is more open at that moment. Always handle wet hair gently and preferably use a wide-tooth comb instead of a brush for detangling.
8. Environment, lifestyle, and hormones
Hair and scalp respond not only to what you apply to them, but also to internal and external factors that have nothing to do with your hair care routine.
Environmental factors
Cold, dry air in winter and air conditioning in summer lower the humidity around the hair, which leads to drying out of the hair shaft. UV radiation affects the structure of the hair and can weaken the cuticle. Wind causes mechanical friction and tangles. This does not mean you should cover your hair, but seasonal adjustments to your routine can be useful.
Stress and nutrition
Chronic stress affects the hair cycle. With ongoing stress, more hairs can enter the telogen phase, the resting phase of the hair cycle, at the same time. This results in more hair shedding than usual, a phenomenon known as telogen effluvium. A shortage of certain nutrients, such as iron, zinc, biotin, or protein, can also affect hair condition, although this is a topic beyond the scope of cosmetic care. You can read more about the hair cycle, the causes of hair loss, and what cosmetic care can and cannot do in our blog on hair loss and the hair cycle.
Hormonal factors and the hair cycle
Hair grows in three phases. The anagen phase is the active growth phase and lasts on average two to six years. The catagen phase is a short transition phase of two to three weeks. The telogen phase is the resting phase, after which the hair sheds and a new cycle begins. Hormones play a decisive role in the duration and course of these phases.
During pregnancy, estrogen prolongs the anagen phase, resulting in thicker, fuller hair. After birth, hormone levels normalize quickly, causing many hairs to enter the telogen phase at the same time: the well-known postpartum hair loss. Menopause, thyroid problems, and other hormonal shifts also affect hair condition. These are medical topics outside the field of cosmetic care, but it helps to understand the background.
How often should you wash?
There is no universal answer to how often you should wash your hair. The ideal rhythm differs by scalp type, hair type, lifestyle, and season. People with an oily scalp wash more often on average than people with a dry scalp. Gradually extending the interval between washes, combined with gentle shampoos, helps normalize sebum production and protect the scalp barrier. More on this in our blog about how often to wash your hair.
9. Gentle care for hair and scalp
A supportive hair routine does not have to be complex. The basics consist of gentle cleansing, targeted scalp care, and protection of the hair shaft. Below we discuss the key steps.
Step 1: Gentle cleansing
The cleanser is the most important step in your hair routine. Shampoos with harsh sulfates, such as sodium lauryl sulfate (SLS), clean effectively but can also strip the lipids from the scalp barrier. Gentler alternatives are shampoos based on sodium laureth sulfate (SLES) or coco-glucoside, which cleanse without stripping the scalp of all its natural oils. For a dry or sensitive scalp, this is the most impactful change to make. Anyone who wants to replace shampoo entirely with conditioner can consider co-washing: you can read more about this in our blog on co-washing and how to start.
Step 2: Oil as a scalp treatment
Plant oils can be used as a pre-wash treatment on the scalp: apply a small amount of oil to the scalp, massage in gently, and leave on for 20 to 30 minutes before washing. This protects the scalp during washing and can help keep the scalp more supple. Preferably use lightweight oils that absorb well, such as jojoba oil or argan oil.
Step 3: Oil on the hair shaft
On the hair shaft, oil works differently than on the scalp. Here, it is about protecting the cuticle and reducing moisture loss from the hair shaft. Apply a small amount of oil to the mid-lengths and ends of dry or slightly damp hair. For curly hair, oil can also be used as a styling product to define the curl without weighing it down. More on this in our blog about natural oils for curly hair.
Step 4: Hydrosols as a scalp mist
Hydrosols can be sprayed onto the scalp as a gentle in-between step between washes. Rose water or lavender water gives a refreshing feeling to the scalp without cleansing or disturbing the sebum balance. This is a gentle option for people who want to freshen the scalp without a full wash.
Step 4b: Periodic deep cleansing with clay
If product residue or limescale buildup from hard water accumulates, an occasional clay mask on the scalp can complement regular cleansing. Clay minerals such as ghassoul and bentonite cleanse through adsorption: they electrically attract impurities and hold onto them until the mask is rinsed off. This is a treatment, not a daily cleanser. You can read more about how to use clay as a gentle exfoliant and when it makes sense in our blog on scalp scrub with clay.
Step 4c: Scalp massage
Regular scalp massage stimulates circulation in the dermis via mechanotransduction: mechanical pressure from the fingertips is converted into cellular signals around the hair follicle. Four to five minutes of daily massage with the fingertips, on dry hair or combined with a pre-wash oil, is a simple but effective addition to the routine. You can read more about the technique, frequency, and the mechanism behind it in our blog about scalp massage.
Step 5: Reduce heat and friction
Use the hair dryer at a lower temperature and keep some distance from the hair. If possible, let the hair air-dry partially before blow-drying. Replace a cotton pillowcase with silk or satin to reduce friction during sleep. Use a wide-tooth comb on wet hair and avoid tight elastics that put pressure on the hair shaft.
10. Which oil suits your hair and scalp?
Not every oil works for every hair type. The choice depends on hair porosity, hair thickness, scalp type, and personal preference for texture. Below is an overview of the oils in the More Natural range and their use for hair and scalp.
Light liquid wax that mimics sebum. Suitable for all hair types, including oily scalps. Non-comedogenic.
Rich in vitamin E and oleic acid. Light enough for the hair shaft, nourishing for the scalp. Suitable for dry and damaged hair. More in our blog about argan oil for hair.
Nourishing and richer. Penetrates the hair shaft well. Suitable for dry, thick, or chemically treated hair with high porosity.
Light, rich in linoleic acid, non-comedogenic. Particularly suitable for fine hair and sensitive scalps. More in our blog about hemp seed oil for hair.
Thick and occlusive. Traditionally used for hair and eyebrows. Preferably diluted with a lighter oil for use on the hair shaft. More in our blog about castor oil for hair.
Rich in palmitoleic acid, a fatty acid also found in the skin. Light, well absorbed, suitable for fine hair and sensitive scalps.
Feels dry despite its nourishing profile. Balanced omega 3-6-9. Particularly suitable for curly and coily hair. More in our blog about baobab oil for hair.
Traditionally used for sensitive skin and scalp. Unique composition with thymoquinone. Preferably used diluted. More in our blog about black cumin seed oil for hair.
Light, rich in linoleic acid. Suitable as a light finishing treatment on the hair ends. Not ideal for the scalp due to faster oxidation.
Combination of argan oil and avocado oil. Specially formulated for hair and scalp.
Want to know which oil works best for your specific hair type? Then read our blog about what makes jojoba oil ideal for hair and face. View the full range of natural oils for an overview of all available oils.
11. Common misconceptions
"An itchy scalp always means dryness"
Itching is one of the most common scalp complaints, but the cause is far from always dryness. Excess sebum production, product residue, a disrupted microbiome, sensitivity to certain ingredients, or increased activity of Malassezia can all lead to itching. The approach differs greatly depending on the cause, so it makes sense to first understand where the itching is coming from before adjusting your routine. You can read more about this in our blog on itchy scalp and possible causes.
"Oil makes the scalp greasier"
This is not true for all oils. Jojoba oil mimics the composition of sebum and is well tolerated by many people with an oily scalp without stimulating sebum production. Heavy, occlusive oils such as castor oil can contribute to a greasy feeling on the scalp if used excessively. The application and choice of oil are decisive.
"Daily washing is necessary for a healthy scalp"
How often washing is necessary differs from person to person. For people with an oily scalp, daily washing may feel necessary, but for people with a dry or sensitive scalp, washing too often can actually weaken the barrier function. There is no universal standard: the ideal washing rhythm is the one where the scalp feels comfortable and the hair stays in good condition.
"Expensive hair is always better hair"
The price of a shampoo or conditioner says little about how gentle it is or whether it suits your scalp type. What matters is the formula: gentle cleansers, no unnecessary irritants, and a formula that matches your specific needs. Learning to read ingredients is more effective than relying on price range or marketing claims.
12. When should you seek professional help?
Gentle care can support many scalp complaints, but some issues require professional evaluation. Consult a dermatologist or GP if you have:
- Persistent or severe flaking that does not respond to gentle changes in your routine
- Painful, red, or inflamed patches on the scalp
- Sudden or diffuse hair loss that is more than normal shedding
- Visible bald patches or a receding hairline
- Severe itching that affects daily functioning
Conditions such as seborrheic dermatitis, scalp psoriasis, alopecia, or fungal infections require medical diagnosis and treatment. Cosmetic care can provide comfort, but it does not replace medical advice.
Frequently asked questions
What is the difference between dry scalp and flakes?
Dry scalp results from a lipid deficiency in the skin barrier and is characterized by small, dry, loose flakes and a tight feeling. Flakes associated with seborrheic dermatitis are larger, greasier, and more yellow in color, and are often accompanied by redness. The cause and approach are fundamentally different: for dry scalp, gentler cleansing and support of the lipid layer help, while seborrheic dermatitis calls for medical evaluation.
Which oil is best for the scalp?
That depends on your scalp type. For a dry or sensitive scalp, lightweight oils that support the barrier without burdening the follicles work well, such as jojoba oil and macadamia oil. For an oily scalp, jojoba oil is a good choice because it mimics the composition of sebum. Black cumin seed oil is traditionally used for sensitive or reactive scalps. Heavy oils such as castor oil are better suited to the hair shaft than to the scalp itself.
How do you use oil on your hair without weighing it down?
Use as little as possible: for most hair types, 1 to 3 drops is enough. Apply the oil to the mid-lengths and ends of dry or slightly damp hair, not to the scalp or roots. Warm the oil briefly between your palms before applying it so it spreads evenly. Choose a lightweight oil that suits your hair porosity: low-porosity hair does better with light oils such as jojoba or argan oil, while high-porosity hair tolerates richer oils better.
How often should you wash your hair?
There is no universal answer. The ideal washing rhythm depends on your scalp type, hair type, lifestyle, and season. People with an oily scalp wash more often on average than people with a dry scalp. As a rule of thumb: wash as little as is comfortable, using the gentlest products possible. Gradually extending the interval between washes helps normalize sebum production in the long term.
What is hair porosity and why is it important?
Hair porosity describes how easily the hair shaft absorbs moisture and other substances. Low-porosity hair has tightly packed cuticles and absorbs moisture slowly but retains it well. High-porosity hair has open or damaged cuticles, absorbs moisture quickly but loses it quickly too. Porosity determines which oils and products work well in your hair: heavier oils work better for high porosity, lightweight oils for low porosity.
Can stress cause hair loss?
Chronic stress can contribute to a condition called telogen effluvium: more hairs simultaneously enter the resting phase of the hair cycle, which after a few months results in increased hair shedding. This is usually temporary and returns to normal when the stress factor decreases. Ongoing or severe hair loss is always a reason to consult a GP or dermatologist.
