Dandruff appears when the scalp sheds skin faster than normal. This can occur for various reasons, such as excessive oil, dry skin, the presence of microorganisms like Malassezia, or scalp irritation. Factors such as sweat, the use of harsh products, or inadequate hygiene can also disrupt the scalp's balance and promote this excessive flaking.
What Dandruff Really Is
Dandruff is an excessive flaking of the scalp.
The skin on the scalp is constantly renewing itself, but when this process accelerates, dead skin cells accumulate, leading to the typical white flakes.
In many cases, dandruff is also accompanied by:
- itchy scalp
- irritation or redness
- tightness or dryness sensation
While usually a mild problem, if not treated correctly, it can become intense or persistent dandruff.
Main Causes of Dandruff in Hair
Dandruff doesn't appear for a single reason. It's usually the result of several factors that disrupt the natural balance of the scalp.
Here are some of the most common causes.
Excess Oil on the Scalp
One of the most frequent causes is excess sebum.
The scalp naturally produces oil to protect the skin and hair, but when this production is excessive, it can favor the appearance of a microorganism called Malassezia.
This microorganism is naturally present on the skin, but when it spreads excessively, it can cause irritation and accelerate skin shedding.
In these cases, what is known as oily dandruff usually appears.
Dry Scalp
In other cases, the opposite occurs.
A scalp that is too dry can cause fine flaking, often accompanied by itching or a sensation of tightness.
This type of dandruff usually appears when:
- shampoos that are too harsh are used
- hair is washed with very hot water
- the scalp loses hydration due to sweat or other causes
In these cases, we refer to dry dandruff.
Incorrect Hair Washing
How you wash your hair also plays a role.
Both washing your hair too frequently with harsh products and not washing your hair if you sweat or residue accumulates on the scalp can disrupt the natural balance of the scalp.
When sweat, oil, or hair product residues accumulate, the scalp can become irritated and promote the appearance of dandruff.
Seborrheic Dermatitis
In some cases, dandruff is related to a condition called seborrheic dermatitis.
This is an inflammation of the scalp that causes:
- more visible flaking
- redness
- itching
This type of dandruff is usually more serious and persistent.
Sweat and Physical Activity
Sweat can also influence the balance of the scalp.
When sweat accumulates on the scalp for many hours and dries on the skin, it creates an environment that promotes irritation and flaking caused by the salts in that sweat.
This is especially common in people who exercise regularly.
Types of Dandruff
Although dandruff is often discussed as a single problem, in reality, there are different types of dandruff, and each can have distinct causes.
Dry Dandruff
It is characterized by small, fine flakes that easily detach from the scalp.
It usually appears when the skin is dehydrated or when overly harsh products are used.
Oily Dandruff
In this case, the flakes are usually larger and are associated with excess oil on the scalp.
It is common for it to be accompanied by itching or a sensation of an irritated scalp.
Seborrheic Dandruff
It is related to seborrheic dermatitis and usually causes more visible and persistent flaking.
In these cases, the scalp may also present reddish or inflamed areas.
What to Do When Dandruff Doesn't Go Away
One of the most frustrating situations is when dandruff does not disappear despite washing your hair frequently.
This usually occurs when the cause of the problem is not correctly identified.
Some recommendations that can help are:
- using a suitable shampoo for the scalp
- avoiding overly harsh products
- maintaining regular hair hygiene
- avoiding sweat accumulation for many hours
If dandruff is very persistent or intense, it may also be advisable to consult a dermatologist.
How to Prevent Dandruff
Preventing dandruff often depends on maintaining the natural balance of the scalp.
Some practices that can help are:
- using gentle shampoos that respect the natural barrier of the scalp
- avoiding overly hot water
