Dandruff is a chronic skin problem characterized by a flaky scalp and varying degrees of itching.
The main causes of dandruff include the overgrowth of the Malassezia fungus, excessive oiliness of the scalp, skin barrier defects, tight clothing around the hair, and hair care habits and products. In addition, it can be influenced by individual factors related to a person.
This article covers the topic of ‘what is dandruff’, the description of its flakes, the causes of dandruff – including its association with the fungus Malassezia, various treatment options, and FAQs.
What is dandruff?
Dandruff is a skin condition characterized by the presence of flaky skin on the scalp, often accompanied by itching. This condition is commonly seen in men.
Dandruff usually appears as thick, yellow, greasy flakes, which contrast with the white, fine flakes typically seen with a dry scalp.
At times, it can be challenging to differentiate between dandruff and other scaly skin conditions, such as seborrheic dermatitis.
Is it a fungal infection?
Dandruff is not a fungal infection. It’s associated with our skin’s sensitivity to by-products of a fungus, Malassezia, which naturally inhabits our scalp.
In some cases, the quantity of this fungus increases, and our skin becomes sensitive to its metabolites, such as free fatty acids, particularly oleic acid. This leads to inflammation, which accelerates the rate of cell proliferation, resulting in dandruff.
In addition to this, the skin underneath the flakes can be thickened, although inflammation is typically minimal. This minimal inflammation is one of the factors that differentiates dandruff from seborrheic dermatitis, which is characterized by redness and inflammation.
Causes
There are several factors that are strongly associated with it. Let’s talk about them.
1. Malassezia (a fungus that lives on our skin)
The role of Malassezia in dandruff is complex. However, the general consensus is that dandruff is associated with the presence of increased Malassezia fungus on the scalp.
Malassezia is part of the normal flora of the skin, so we all have it on our skin. The mere presence of Malassezia is not what causes dandruff. Probably, there is an interplay of several other factors.
Malassezia is a lipid-loving fungus and it can eat and digest our sebum lipids with the enzyme lipase. This can lead to the release of free fatty acids like oleic acid, which can cause barrier disruption, increased turnover of skin cells, irritation, and flakiness.
But just applying plain oleic acid on the skin of people without dandruff doesn’t produce any flakiness, contrary to what happens in people with dandruff.
So, the underlying skin and individual susceptibility (for example, how their immune system responds to Malassezia) play some role in this condition.
2. Oily scalp
Dandruff is strongly correlated with increased activity of the oil glands, which are mostly under the control of hormones. However, not all people with oily scalps have dandruff, and some people with normal sebum secretion can also have dandruff. So, while there is a strong correlation, it is not the definitive cause.
Another factor, that might be related, is the difference in the composition of surface lipids. This could potentially make an individual more susceptible to the effects of Malassezia.
3. Skin barrier dysfunction
Individual susceptibility is mainly influenced by the barrier function of the skin and the individual’s immune response.
Research suggests that people with dandruff have some degree of barrier dysfunction, which makes them more susceptible to the effects of Malassezia and thus, contributes to dandruff.
4. Stress
Stress can have a significant impact on your overall health, including the health of your scalp. It can affect the immune system, which in turn can exacerbate skin conditions, including dandruff.
Moreover, stress can cause changes in hormones that regulate skin and hair follicles, contributing to flaking and itching.
5. Sleep deprivation
Lack of sleep can weaken the immune system and impact hormone regulation, both of which can contribute to a dandruff flare-up.
Adequate sleep is important for body regeneration, including skin renewal processes, which can be disrupted when you’re not getting enough rest.
6. Neurogenic factors
Neurogenic factors relate to nerves and their functioning. Conditions that affect the nervous system, like Parkinson’s disease, have been associated with a greater likelihood of dandruff and other skin issues. This might be due to changes in skin sebum (oil) production or reduced ability to remove dead skin cells.
7. Certain medications
Some medications can also contribute to dandruff, such as lithium, certain anti-cancer drugs, and immunosuppressants.
It is thought that lithium can affect the skin’s oil production, potentially causing the overproduction of sebum, an oily substance that can promote the growth of the dandruff-causing fungus.
8. Excessive exposure to the sun
While moderate sun exposure can be beneficial for certain skin conditions, excessive exposure can lead to damage and dryness, which can make dandruff worse.
UV rays from the sun can damage the scalp’s outer protective layer, leading to increased water loss and dry, flaky skin.
9. Hair care products and habits
Shampoos do not directly cause dandruff. However, if shampoo irritates your scalp, it can make your dandruff worse.
If a shampoo is based on heavy oils and you don’t rinse it well, the residual oils may contribute to dandruff.
Similarly, if you use hair care products that are based on oils and you don’t rinse them or leave them on for long, this can create a favorable environment for the yeast Malassezia to flourish and grow, contributing to dandruff.
Your shampooing habits can also greatly affect your scalp health. Many people think that dandruff indicates dry skin, so they decrease the frequency of shampooing.
However, not shampooing regularly can cause the buildup of oil and dead skin cells on the scalp, which Malassezia can feed on and potentially worsen dandruff.
10. Clothing
Clothing around the head, such as caps, scarves, and hats can trap heat and moisture, making the scalp more susceptible to the growth of Malassezia. Therefore, it’s a good idea to opt for headwear made of breathable materials.
11. Nutrition
While there’s no direct evidence linking diet to dandruff, diets deficient in B vitamins, zinc, and omega fatty acids can affect scalp health.
Taking the above factors into account, although some individual factors cannot be altered by applying skin care products, targeting Malassezia with anti-dandruff shampoos or leave-on products, coupled with certain lifestyle changes, can help manage this condition.
Why is your dandruff severe?
If left untreated or if you use excessively oily products, which exacerbate dandruff, your dandruff can appear bad or severe. If you see flaky patches elsewhere like on your face, inside the ear canal, or on your chest, you might be dealing with another skin condition called seborrheic dermatitis.
In addition, if your dandruff appears suddenly, like after you use a hair care product and you see a flaky scalp in the morning, the cause may not be just dandruff. It could be due to irritation of the scalp leading to another skin condition called contact dermatitis.
Is it bad for you?
Dandruff is not bad or harmful, but it can affect an individual’s lifestyle. The itching it causes can impact the quality of life. Persistent scratching can also cause scabs and sores to form on the scalp.
The flakes can often be seen in the hair or on the shoulders, especially when wearing dark clothing. This can cause embarrassment and impact a person’s self-esteem.
Furthermore, while it doesn’t directly cause hair loss, scratching and stress can contribute to hair damage and potential hair loss over time.
Treatment
The treatment of dandruff focuses on reducing Malassezia and eliminating dead skin cells. Additionally, certain lifestyle changes can prove beneficial.
1. Reduce Malassezia
Ingredients such as zinc pyrithione, ketoconazole, selenium sulfide, and piroctone olamine can decrease the presence of the Malassezia fungus on the scalp, which in turn reduces symptoms of itching and scaling.
2. Remove scales
Ingredients such as salicylic acid, sulfur, and coal tar can help reduce the buildup of dead skin cells. This can also enhance the penetration of other ingredients.
3. Scalp and hair care
Contrary to common belief, dandruff is not caused by dry skin, so make sure to shampoo your hair several times a week to eliminate excess oils. If you have a sensitive scalp, ensure to patch test each new product.
4. Stress management
Stress can lead to dandruff flare-ups. Hence, it’s important to engage in stress-reducing activities that you enjoy, such as listening to music or going for walks. Also, make sure you get a good night’s sleep.
For more details, refer to this post on dandruff treatments.
FAQs
Where does dandruff come from?
Dandruff comes from our own skin. The fungus Malassezia can irritate our skin with its by-products, causing irritation that results in increased production of skin cells. These cells do not fall off but clump to form flakes and scales, known as dandruff.
Is dandruff contagious?
No, dandruff is not contagious, and it cannot spread to others. It occurs due to an individual’s skin reacting to something, and not everyone’s skin reacts the same way to Malassezia.
Furthermore, Malassezia is part of the normal skin flora, so we all already have it.
Can dandruff cause hair loss?
Dandruff itself does not cause hair loss. However, conditions like telogen effluvium or androgenetic alopecia may be accompanied by dandruff. Additionally, dandruff is often associated with intense itching.
As a result, frequent or aggressive scratching can traumatize our hair follicles, potentially leading to hair loss. Fortunately, some anti-dandruff ingredients, like ketoconazole, can also be helpful for hormone-related hair loss, also known as androgenic alopecia.
Summary
Dandruff is thought to be caused by an increased presence of the fungus Malassezia, excessive oiliness of the scalp, skin barrier dysfunction, and an individual’s immune response.
Maintaining a gentle scalp care routine is essential if you are dealing with this condition. There are multiple beneficial ingredients available and you might have to experiment to find what works best for you.
If you notice increasing flakiness and visible redness, it’s important to consult a healthcare provider for an appropriate diagnosis and treatment.
References
- Ranganathan S, Mukhopadhyay T. Dandruff: the most commercially exploited skin disease. Indian J Dermatol. 2010 Apr-Jun;55(2):130-4. PMID: 20606879; PMCID: PMC2887514.
- DeAngelis, Yvonne M. et al. “Three etiologic facets of dandruff and seborrheic dermatitis: Malassezia fungi, sebaceous lipids, and individual sensitivity.” The journal of investigative dermatology. Symposium proceedings 10 3 (2005): 295-7.
- Borda LJ, Wikramanayake TC. Seborrheic Dermatitis and Dandruff: A Comprehensive Review. J Clin Investig Dermatol. 2015 Dec;3(2):10.13188/2373-1044.1000019. Epub 2015 Dec 15. PMID: 27148560; PMCID: PMC4852869.
- Harding CR, Moore AE, Rogers JS, Meldrum H, Scott AE, McGlone FP. Dandruff: a condition characterized by decreased levels of intercellular lipids in scalp stratum corneum and impaired barrier function. Arch Dermatol Res. 2002 Jul;294(5):221-30. Epub 2002 Jun 7. PMID: 12115025.
Disclaimer: This blog post is for information purposes only and does not replace medical advice.