What Causes Dandruff?

Dandruff is a very common skin condition that affects almost half of the world’s population. In a majority of cases, it’s harmless and doesn’t cause issues beyond itchiness and discomfort.

Despite this, people suffering from this condition often go out of their way to get rid of it. Depending on the amount and size of the flakes, dandruff can be quite embarrassing to many. And since it’s a chronic condition, many people find it hard to manage.

The main reason for this is a lack of knowledge about the causes of dandruff. Since there are a few of them, the same remedies won’t yield equal results to everyone. This is why understanding what causes dandruff is essential to overcoming it.

Main Causes of Dandruff

Generally speaking, dandruff is caused by scalp skin shedding too fast. Skin shedding is a normal and healthy process as dead cells are replaced by the new ones. However, if this process occurs at a faster rate than it should, the skin cells clump and form white flakes.

There are multiple underlying causes of this process. Let’s see what they are and the possible treatment for each of them.

Seborrheic Dermatitis

Seborrheic Dermatitis is an inflammatory disease that’s usually localized the head and trunk. This is because sebaceous glands are present in abundance in these regions, and it’s these glands that are in charge of producing an oily substance that lubricates the skin. But they can also act up and cause seborrheic dermatitis.

Even though the cause of this disorder isn’t well-understood, experts agree that there are several factors that play a role:

  1. Hormonal changes
  2. Harsh chemicals and soaps
  3. Stress
  4. Certain medications
  5. Dry weather

There isn’t a specific way of diagnosing seborrheic dermatitis. Instead, physical examination of skin and skin biopsy are used to rule out the other disorders that present themselves in a similar fashion. After the diagnosis has been made, there are several treatment options.

In most cases, alternately using a regular shampoo and a medicated shampoo formulated for the condition should solve the problem. In more serious cases however, topical corticosteroids might be necessary. In cases where corticosteroids can’t be used, non-steroidal topicals will be given.


Malassezia is a group of yeasts that can be found in the skin of almost all warm-blooded animals. They’re an essential part of skin microbiota, and on their own, they aren’t necessarily an issue. However, this group of yeasts has been associated with a variety of skin conditions, including dandruff.

Our skin is completely covered in bacteria and fungi. The interactions between these microorganisms determine whether Malassezia will cause skin disorders or not. Separating it from the rest of the skin flora is an extremely challenging task, which is why there’s currently no concrete knowledge about the way these interactions occur.

What is known, however, is that Malassezia causes excess growth of skin cells, thereby speeding up the process of skin shedding, which results in dandruff.

As far as treatment goes, antifungals are the obvious solution. However, the goal of such medications isn’t to eradicate Malassezia, as it’s still a healthy part of the skin microbiota. Instead, the remedy should only keep it under control long enough for the symptoms of dandruff to go away, after which the skin flora balance should be restored.

Dry Skin

Much like oily skin can cause dandruff, dry skin can as well. Also known as xerosis, dry skin is among the most common causes of dandruff. As to why this might happen, there’s a variety of causes, including:

  • Heat
  • Dry weather, low humidity
  • Hot showers
  • Harsh hair products
  • Other skin conditions

Dandruff is only one of the possible results of dry skin. There are several other complications which might either feel like dandruff or develop into something more serious, such as a variety of infections. When the skin is dry, it tends to crack, which allows the fungus and bacteria that live in it to enter the body.

Fortunately, this doesn’t happen often, and there are many ways of dealing with dry skin, depending on the cause. One of the main ones is using a moisturizing shampoo while washing the hair with cold to medium-hot water.

Another possible solution is taking more vitamin B since it promotes healthy skin. If dry skin becomes a serious issue that doesn’t seem to go away, a visit to the doctor might be a good idea.

Scalp Psoriasis

Scalp psoriasis is a skin condition that can be completely harmless, but it can also develop into a more serious issue. The cause of skin psoriasis is related to immune system issues, where skin cells grow too quickly and form patches.

Not only does skin psoriasis cause flakes that look a lot like dandruff, but it can also make a person more susceptible to it. Moreover, it makes the issue even worse, so treatment might be more complex.

Among the most effective remedies for scalp psoriasis are topicals, such as salicylic acid. This medication is used to treat a majority of skin conditions where an overgrowth of skin cells is present, so it’s a very effective treatment option for dandruff.

If the problem persists for a long time and doesn’t respond to several treatment options, outpatient treatment might be necessary. Depending on the severity of the issue, the patient might undergo steroid injections, as well as laser or non-laser phototherapy. The options are reserved for the most serious of cases, and a majority of scalp psoriasis sufferers resolve the issue with over-the-counter solutions or prescription medication.

The Final Word

These are the most common reasons behind dandruff. Of course, there are more of them, but the above issues are the ones affecting the majority of people that have dandruff issues.

Anti-dandruff shampoos are often all that is needed for this issue to go away. They contain a variety of ingredients that target different issues, so consulting an expert before buying one is recommended. As for the other treatment options, the best remedy will depend on the underlying cause, so a visit to the doctor is a good idea, even if the symptoms aren’t serious.