Hair: where does dandruff come from?
Dandruff is a small white flake found on the scalp or at the roots, often causing discomfort and embarrassment. It is caused by an acceleration of the scalp's cell renewal cycle .
Normally, scalp skin renews itself in about 28 days. In some people, this cycle accelerates to as little as 10 days: new cells push out the old ones before they're ready to fall off. These dead cells accumulate, mix with sebum, and form small flakes called scales —the infamous dandruff.
These flakes detach from the scalp, lodge in the hair, and then fall onto the face and clothes. Contrary to popular belief, the appearance of dandruff has nothing to do with poor hygiene . Anyone can get it, even with a careful hair care routine.
Dandruff is benign and not serious, but it can be unsightly, cause itching and affect the comfort of the scalp.
The three types of dandruff
There are three main types of dandruff: dry dandruff , oily dandruff and seborrheic dermatitis .
1. Dry dandruff
Also called dandruff or pityriasis simplex , dry dandruff appears on dry or sensitive scalps . It is fine, light, and easily falls off the shoulders. It often causes mild itching and a visible powdery effect on the roots.
2. Oily dandruff
Thicker and yellowish, oily dandruff is linked to excessive sebum production . It adheres to the scalp, sometimes forming small patches that itch or irritate. Its presence may be accompanied by a greasy appearance of the roots and a feeling of persistent discomfort.
3. Seborrheic dermatitis
This is a more severe form of dandruff. Seborrheic dermatitis causes inflammation of the scalp , abundant production of oily dandruff, and severe itching. In this case, it is recommended to consult a dermatologist for appropriate treatment.
Causes and risk factors
There are several causes that can explain the appearance of dandruff:
- The presence of a natural scalp yeast, Malassezia , which multiplies excessively;
- Hormonal imbalance or overproduction of sebum;
- Skin diseases (psoriasis, eczema, dermatitis);
- Chronic stress or lack of sleep;
- An unbalanced diet or one too rich in fat;
- Using irritating hair products or overly harsh shampoos.
Dandruff can also worsen with seasonal changes, pollution or rinsing water that is too hard.
How to get rid of dandruff?
Good news: there are simple actions and suitable treatments to restore a healthy and soothed scalp .
1. Space out shampoos
Washing your hair every day weakens your scalp. In response, your sebaceous glands produce even more sebum, promoting the proliferation of dandruff. Ideally, you should limit your shampoos to twice a week and use a gentle, anti-dandruff product suited to your scalp type.
2. Choose a suitable shampoo
Anti-dandruff shampoos containing zinc pyrithione, salicylic acid, or nettle extract help regulate sebum and soothe irritation. For a more natural approach, consider formulas enriched with essential oils or purifying plants such as rosemary, tea tree, or thyme.
3. Use soothing natural treatments
To soothe and moisturize the scalp, treatments based on vegetable oils are particularly effective. Jojoba oil, for example, regulates sebum without leaving a greasy feeling. You can add a few drops of Atlas cedar or tea tree essential oils for a purifying effect.
Oil baths should be left on for several hours before shampooing. Plants such as thyme or aloe vera soothe itching and rebalance the scalp flora.
4. Take care of your lifestyle
A balanced scalp also depends on overall health. A diet rich in B vitamins, zinc, and omega-3 helps naturally regulate sebum and strengthen the skin barrier. Stress, fatigue, and smoking can increase dandruff production; learning to better manage these factors contributes to a healthier scalp.
5. Avoid harsh products
Mousses, hairsprays, and setting gels often contain alcohol or silicones that suffocate the scalp. It's best to avoid them during periods of dandruff imbalance. Choose natural, lightweight products and rinse your hair thoroughly after each treatment.
If dandruff persists despite these precautions, it is advisable to consult a pharmacist or dermatologist to identify the exact cause and adapt the treatment.
FAQ – Dandruff and Scalp
Is dandruff related to stress?
Yes. Stress alters sebum production and weakens the scalp's defenses, creating a breeding ground for dandruff.
Should you wash your hair more often to get rid of dandruff?
No. On the contrary, too much shampooing can unbalance the scalp. It's better to use a gentle anti-dandruff treatment twice a week.
Can dandruff cause hair loss?
Indirectly, yes. An irritated and inflamed scalp can weaken the roots and increase hair loss. That's why it's important to treat dandruff as soon as it appears.
