Suffering from an oily scalp means having hair that looks "dirty" every night, a haircut that loses its allure as the day goes on... These inconveniences often lead to the urgent need to wash your hair every day!

This is all due to an excessive secretion of sebum. When it is produced in abundance by the scalp, sebum will grease the hair roots, which will become heavy and stick together.

Today's society places great importance on appearance. To meet these physical criteria, which are dictated to us by current beauty trends, hair must be healthy, resistant and shiny.

However, it’s very difficult to meet this criterion when the scalp is greasy.

Faced with hair that gets greasy too quickly, certain beauty gestures are repeated day after day. The aim is to regain the lightness and natural shine of the hair—for the long term.

Oily scalp: excessive sebum production

The scalp becomes oily when it suffers from hyper-seborrhea.

Before discussing the causes and consequences of this hyper-seborrhea on the scalp, it’s important to clarify the role of seborrhea itself.

Scalp seborrhea: a complex mechanism

Seborrhea is the natural process of sebum secretion by the sebaceous glands. It performs several functions on the skin, and therefore on the scalp.

It’s a physiological phenomenon whose essential role is to protect the hair shaft and the scalp.


Sebum is a natural and necessary element for the proper functioning of this organ: the skin.

Sebum is a substance secreted by the sebaceous glands, which are particularly large and abundant in the scalp. There are between 400 and 900 per cm². Sebum is essential for the good health of the scalp and hair.

It has a true protective function without which the scalp and hair would become dehydrated. Without sebum, the scalp would be extremely tense and the hair very fragile and brittle.

Sebum is therefore necessary to keep the hair beautiful, soft and naturally shiny.

It's a greasy substance, as it's very rich in lipids:

  • 57.5% triglycerides
  • 26% waxes
  • 12% squalene
  • 5% cholesterol

Sebum spreads over the outermost layers of our body, particularly on the surface of the skin and hair. It thus provides both a barrier function against external aggressions and helps retain water.

The sebaceous gland is a production plant

It can be broken down into 2 main parts:

  • the hair shaft, which is the visible part of the hair
  • the hair follicle, the true internal, deep and living root of the hair, which is implanted in the dermis. It itself is composed of:
    • the hair bulb, which is responsible for the synthesis of keratin and hair
    • the sebaceous gland, which produces sebum that is transported through the sebaceous duct to the hair bulb, then onto the scalp and along the hair shaft.



The stages of seborrhea

Here are the stages of this process:

1. Testosterone is transported to the hair follicle

Testosterone is an androgen that is present in both men and women. It is involved in various metabolisms in the human body. It’s carried in the blood and is activated in the hair bulb. Once in the sebaceous gland, it passes through the cell membranes of its constituent cells.

2. The role of 5α-reductase

In the cell, testosterone interacts with a lipophilic enzyme, 5-alpha-reductase. This enzyme converts testosterone into dihydrotestosterone (DHT).

3. Stimulation of the sebaceous gland

DHT has a particular molecular form that allows it to bind to its own receptors located on the nucleus of the cell. The binding of DHT to the nucleus sends a message to the cells: the signal to produce sebum.

The case of hyper-seborrhea causing an oily scalp

The signs of an oily scalp

Scalp seborrhea is a metabolic phenomenon that functions in a "stimulation-response" mode. Its purpose is to permanently protect the surface of the scalp and the hair shaft.

However, its fluctuations – whether in excess or a deficiency – can lead to imbalances. When the rate of sebum production is higher than average, we speak of hyper-seborrhea.

A scalp can be characterized by its level of sebaceous excretion:

  • dry scalp: less than 120 mg/cm².
  • normal scalp: from 120 to 190 mg/cm².
  • oily scalp: above 190 mg/cm².

Factors that trigger hyper-seborrhea

There are various causes that can promote or accentuate hyper-seborrhea.

A genetic factor: hyperactivity of the sebaceous gland.

The sebaceous gland is actually an androgen-dependent organ. This means that androgens (or male hormones) are the main stimulus for the sebaceous gland. This hyperactivity may therefore be caused by:

  • either an increase in circulating androgens. This is the least frequent case. It is then a real pathology;
  • or isolated hyperactivity of 5α-reductase, which leads to a deregulation of sebogenesis.

External aggressions: climatic or chemical

  • pollution, prolonged exposure to the sun
  • styling, blow-drying with too much heat
  • unsuitable, irritating hair care products that strip the scalp and cause reactive hyper-seborrhea.

Emotional stress, nervous tension exacerbating the sebaceous function.

Certain medications: antibiotics, diuretics, anticoagulants.

Certain diseases: such as Parkinson's disease.

Endocrine disorders.

The consequences of an oily scalp are not only aesthetic

The main inconveniences of hyper-seborrhea are certainly aesthetic.

People with an oily scalp complain, first and foremost, that their hair is difficult to style and that it’s impossible to keep it place for long. Their hair is flat, dull and lacks volume.

In fact, the hair is weighed down at the roots, as if overloaded by this excessive sebum. It loses its lightness and shine. It clumps into strands. It no longer breathes and takes on a heavy appearance.

But the excess sebum secreted also leads to skin complications.

It leads to the proliferation of lipophilic saprophytic flora, made up of bacteria and yeast. This flora, through the lipases it produces, hydrolyzes the triglycerides in the sebum into free fatty acids.

These fatty acids are irritants. They provoke an inflammatory reaction that keeps stimulating the sebaceous gland, and therefore leads to hyper-seborrhea. It is a vicious circle!


Hyper-seborrhea can also lead tohair loss.

The mechanical action of styling or shampooing (depending on the treatment used) will lead to the excess sebum produced clogging the pores of the scalp and blocking the sebaceous glands. The supply of oxygen and nutrients to the hair follicles is then reduced.

In the long run, the hair can suffer from this poor nutrition, become exhausted and fall out. It’s therefore necessary to act as soon as possible to limit or stop hair loss.

How to treat an oily scalp

These sebum hypersecretion problems are highly sensitizing.

Those who experience them need a proper care program to treat both the symptoms and the cause of the problem.

In Europe, 19% of women have an oily scalp. Men are also affected, with 21% experiencing the same problem.

To restore their hair's health and beauty, these people need effective oil-fighting hair products adapted to their situation.

We recommend choosing an ultra-gentle shampoo with a neutral pH that meets a few criteria:

  • eliminates sebum and provides a clean, fresh feeling from the first use
  • restores balance to the scalp
  • reduces the frequency of shampooing.

Curbicia: pumpkin seed, an oily scalp's best friend

Among the natural active ingredients available to us, curbicia – or more simply pumpkin seed oil – plays an exceptional role in the fight against the sebum overproduction responsible for an oily scalp.

It acts on two complementary levels.


Firstly, it reduces the production of lipids by the sebocytes of the sebaceous gland.

Secondly, this active ingredient inhibits the enzyme that transforms testosterone into a signal in the sebaceous glands. In fact, testosterone (this androgen) is involved in the sebum production process. It’s transformed in the sebaceous glands to become a sebum production signal.

This is where curbicia comes in: it reduces the transmission of this signal by taking the place of this enzyme at the receptor. This way, the sebum overproduction order is blocked!

Whether using a shampoo or a specialized treatment, the first concrete sign that the product is really working its magic is that the user can space out the frequency of their shampoos.



Oily scalp: helpful tips!

Tip 1: Avoid rubbing the scalp, as this activates microcirculation and brings sebum to the surface.

Tip 2: Space out your shampoos. Alternate with a dry shampoo that absorbs both impurities and excess sebum. Lightweight hair and volume are restored!


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