Why Do I Get Dandruff?

I’m sure you have either suffered from dandruff or you know someone who has, as dandruff is a really common skin condition. But have you ever wondered what causes dandruff and how it can be effectively treated?

Well, dandruff is a common and nonserious skin condition that affects many people. It is not contagious, and today is a condition that is accepted to be multifactorial in origin. Some of the possible factors causing dandruff include genetic susceptibility, colonization with yeast (Malassezia species), imbalance of bacterial species, a disrupted epidermal barrier function, increased sebum and peroxidation of squalene, inflammation and other skin conditions. Usually, dandruff can be treated effectively with the right approach.

If you found this information interesting, and you want to help to achieve a healthy, flake-free scalp keep on reading. In this article, We’re going to share with you some of the main causes, symptoms, risk factors and how to treat dandruff effectively.

Overview

Dandruff is a skin condition mostly restricted to the scalp, which is characterised by itchy and flaky skin.¹ Dandruff is a common condition that affects around 50% of the adult population globally. According to research, dandruff commonly begins during puberty and reaches its highest incidence and severity around the age of 20.¹ However, it tends to grow less common among individuals over the age of 50. Studies have also shown that the incidence of dandruff can vary among different ethnic groups.¹

Causes of dandruff

Dandruff is not contagious, and today is a condition perceived as multifactorial.² Some of the factors behind dandruff that have been given more attention are:

Genetic susceptibility 

• Genetics may play a role in the development of dandruff, as  487 genetic markers have been associated with this condition²

Colonization with yeast (Malassezia species) 

• Malassezia species are yeast organisms commonly found on healthy human skin, especially on the scalp. They are known to have an association with dandruff and are dependent on the  sebum lipids from the human scalp as their main nutrient source 
• They break down the oils on the skin, which can lead to inflammation and an overgrowth of skin cells, causing dandruff. The exact mechanism behind how Malassezia causes dandruff and skin irritation is still unclear²

Imbalance of bacterial species 

• Cutibacterium and Staphylococcus are the most dominant commensal bacteria on the scalp. The specific interactions between Malassezia, Staphylococcus, and Cutibacterium are not well understood, but it is suggested that a change in the balance of scalp skin bacteria can contribute to dandruff
• It is suggested that restoring the balance of these bacteria on the scalp may be a way to treat dandruff²

Disrupted epidermal barrier function 

• The epidermis of the dandruff-affected scalp displays significant morphological changes when compared to a healthy scalp. A dry scalp is another feature of dandruff and is reflected by a decrease in ceramides, fatty acids, cholesterol, and barrier integrity proteins in the epidermis.³ The exact sequence of events leading to dandruff remains unclear and a challenge for future research²
• Increased sebum and peroxidation of squalene – sebum is a mixture of lipids produced in the sebaceous gland and released onto the skin surface. In dandruff, the squalene in sebum is peroxidized, leading to increased levels of a substance called squalene monohydroperoxide (SQOOH). Studies have shown that SQOOH can damage the scalp and induce inflammation²

Inflammation

• Yeasts, like Malassezia, can lead to inflammation, as mentioned before. The host's immune response is another key factor in dandruff pathogenesis, as there is a tissue infiltration of immune cells called leukocytes in dandruff tissue, which indicates mild inflammation. There is also an increase in some epidermal inflammation markers in dandruff-affected scalps²

Other skin conditions

Some other skin problems such as eczema, seborrhoeic dermatitis or psoriasis can cause dandruff.

Signs and symptoms of dandruff

Dandruff is characterized by a number of symptoms that can vary in severity depending on the individual.¹ Some of the most common signs of dandruff include:

• Disperse skin flakes on the scalp or hair, which sometimes can spread to the eyebrows, beard or moustache, shoulders and behind the ears
• An itchy scalp
• Infants may also experience scaly, crusty scalps known as cradle cap¹  

Factors such as stress and cold and dry seasons can exacerbate the symptoms of dandruff and make them more severe.¹  

Risk factors

As mentioned before, dandruff is a common condition that can affect people of all ages, but certain factors may make some individuals more susceptible to developing the condition.  

• Age is a significant risk factor, as dandruff tends to begin in young adulthood and continue through middle age. However, it's important to note that dandruff can be a lifelong problem for some individuals
• Gender also plays a role, as dandruff is more common in males than in females
• Certain illnesses and health conditions may also increase an individual's risk of developing dandruff. These include Parkinson's disease and other conditions that affect the nervous system, as well as HIV or a weakened immune system

Treatment for dandruff

The goal when treating dandruff is to eliminate visible symptoms, reduce itching, and maintain remission through ongoing therapy.¹  

If you are experiencing mild dandruff, one of the first steps you can take is to try to cleanse your scalp more regularly with a gentle shampoo to decrease the accumulation of sebum and dead skin cells.⁵ If this does not provide relief, you may want to consider using a medicated dandruff shampoo, which are specifically formulated to target the symptoms of dandruff.

Dandruff shampoos come in various forms and are classified based on their active ingredients. Some shampoos are available over the counter, meanwhile, others require a prescription.⁵ The most common types of dandruff shampoos include:

• Zinc pyrithione shampoos: These contain an antibacterial and antifungal agent
• Coal tar shampoos: these shampoos help slow down the rate at which skin cells on the scalp die and flake
• Salicylic acid shampoos: These help with the elimination of scaling
• Selenium sulphide shampoos: These shampoos also contain an antifungal agent
• Ketoconazole shampoos: These shampoos work by killing dandruff-causing fungi, like Malassezia
• Fluocinolone shampoos: These contain a corticosteroid that helps to control itching and flaking

When to see a doctor

Usually, dandruff can be treated without the need to consult a healthcare professional. So, when should you be seeing your doctor?

• When even though you have been using anti-dandruff shampoo for over a month, you are still experiencing symptoms of dandruff, such as flaking or itching on your scalp
• When you have flaky and itchy patches on other parts of your body other than your scalp
• When your scalp presents redness or is swollen
•  When you have a very itchy scalp and a lot of dandruff

It is advisable to visit a doctor to have your scalp checked for any underlying skin conditions that could be the cause of your persistent dandruff symptoms.

Summary

Dandruff is a skin condition, mostly restricted to the scalp, that involves itchy and flaky skin. Dandruff is a common condition that affects around 50% of the adult population globally.  Some of the most common signs of dandruff include dispersed skin flakes on the scalp or hair, which sometimes can spread to the eyebrows, beard or moustache, shoulders and behind the ears and an itchy scalp. Factors such as stress and cold can exacerbate the symptoms of dandruff. 

Although dandruff is quite common, there are certain factors that may make some individuals more susceptible to developing the condition, such as age, gender and certain illnesses and health conditions (like Parkinson’s or HIV). 

In most of the cases, dandruff can be treated effectively with the right approach.  If you are experiencing mild dandruff, try to cleanse your scalp more regularly with a gentle shampoo. If this does not provide relief, you may want to consider using a medicated dandruff shampoo. If, even after using a medicated shampoo for some time, your dandruff symptoms persist, you should visit a doctor to have your scalp checked for any underlying skin conditions.