How to get rid of dandruff – and fast?

Dandruff, or seborrheic dermatitis, as it is referred to in dermatology is a scalp condition impacting anywhere between 40% to 60% of adults worldwide(1). It is an excessive peeling (desquamation) of the scalp where, instead of releasing only a single cell, (a mature corneocyte) the scalp generates larger, visible concentrations of hundreds or thousands of cells. A wide-reaching study of more than 20,000 women aged from 15 to 75, found dandruff is most common between the ages of 15 to 34, and that after the age of 45, incidence declines(2).

The scalp microbiome - and dandruff
To understand why we get dandruff, we must first recognize the scalp hosts a world of its own. Each square centimeter is home to between 10,000 to 100 million microorganisms – principally bacteria and yeast(3). This ecosystem is referred to as the scalp microbiome. Research has allowed experts to pinpoint which of these microorganisms plays a significant role in dandruff: a certain strain of yeast called Malassezia. This yeast is found to dominate the microbiome on scalps of people with dandruff(4).

Recognizing two types of dandruff
There are two types of dandruff. Dry dandruff and oily dandruff – known as adherent dandruff– for the self-explanatory reason that it tends to stick onto the scalp. Dry dandruff, characterised by its flaky texture and fine, whitish or grey particles, tends to fall liberally.  Greasy or adherent dandruff, on the other hand, where thicker, stickier and more oily flakes accumulate on top of each other, occurs when there is an overproduction of sebum on the scalp.  Adherent dandruff is generally recurring since sebum promotes the development of the Malassezia yeast, creating a vicious circle. Both types of dandruff can irritate, although this is not always the case.

Exploring the reasons for dandruff?
Dandruff occurs for a number of reasons.  First it is important to check it is not in fact psoriasis, an inflammatory skin condition, when intense flakiness can be accompanied by irritated redness. Various factors: from stress to hormonal changes, to a disturbance in the skin’s PH balance, to the scalp drying out from winter central heating, are all implicated in the excess sebum production involved in dandruff and to a scalp environment favorable to colonization by the Malassezia yeast. In fact, winter, is known as the “dandruff season” in temperate regions(5) while dry season exacerbates dandruff in Thailand for instance(6).

It’s important to reset the equilibrium of the scalp microbiome. Stop everything you’re using on your hair. Using shampoos that are too aggressive for your scalp can dry it out and cause irritation and sebum overdrive, creating an imbalance where Malassezia thrives. Harsh formulas create sensitivity, triggering inflammation and fresh dandruff outbreaks. So give your scalp a break. Forgo all unnecessary styling products for now. Switch to a mild shampoo and conditioner, preferably an anti-dandruff formula with a neutral pH.

Choose a fast-working, effective anti-dandruff shampoo
When deciding on anti-dandruff treatment, opt for shampoos concentrated with dermatological actives proven to be effective on dandruff, such as Selenium Sulfide the star active in Vichy’s anti-dandruff products to start freeing the scalp from flakes, from the first wash. Further actives include Zinc and Piroctone Olamine, both known anti-fungal treatments to tackle yeast. From as soon as one day after first use, an anti-dandruff formula should soothe an itchy, angry scalp. From second use, there should be a decline in visibility of flakes on both hair and scalp, thanks to a decrease of Malassezia yeast, while the rest of scalp’s natural bacterial communities remain unimpacted. Using these shampoos quickly helps dandruff scalps look and be free from flakes.

Scalp scrubs for adherent dandruff
The fastest way to tackle adherent dandruff is a scalp scrub. This exfoliation technique helps remove the thick, yellowish flakes that stick to the scalp and roots.  Scrub-based treatments rather than a traditional anti-dandruff shampoo can help remove these fatty oils that have consolidated into the trickiest flakes and encourage your scalp back to health. Look for scrubs with naturally exfoliating ingredients, such as Salicylic Acid to help beat greasy, adherent dandruff long-term.

Rinse it out
You may need to also think about the way you wash your hair. Make sure you rinse your hair completely after washing as residues can irritate. Beware of intense sun exposure which can dry the scalp and lead to flaking. Opt for sulfate-free, alcohol-free formulas, avoiding known irritants completely, such as essential oils and foaming agents. If your dandruff persists, consult a dermatologist.

1. D Saint-Leger. Dandruff (Pityriasis capitis simplex) : of yeasts and men. In : The science of hair care . C Bouillon and J Wilkinson Eds. Taylor and Francis, Boca Raton London New York Singapore. Chapter 21, 609-632, 2005. And J R Schwartz et al. A comprehensive pathophysiology  of dandruff and Seborrheic Dermatitis - towards a more precise definition of scalp health. Acterdermvenerol 2013.
2. Source : Beauty trackWomen 12 pays (2016) & beauty track Men 6 pays (2013), IPSOS pour L’Oréal Recherche. Focus Europe et USA: more than 20000 femmes, 15 à 75 ans. b. Bilan antipelliculaires - CMI- mai 2012
3. Saint-Léger, Clavaud C. et al., The Human Scalp and Related Cosmetic Care Products, Basic Science for Modern Cosmetic Dermatology, Penguin books, 13: 167-178, 2015.
4.Mc Ginley et al. Quantitative microbiology of the scalp in non dandruff, dandruff, and seborrheic dermatitis. J Invest Dermatol , 64:401405, 1975.
5. Robbins C.R. et al., Dandruff, Scalp flaking and Scalp Care, Chemical and Physical Behaviour of Human Hair, Springer, 5th ed., 6:11, 420, 2012.
6. Harding C. R.et al., Dandruff : a condition characterized by decreased levels of intercellular lipids in scalp stratum corneum and impaired barrier Function. Arch Dermatol Res. 294 : 221-230, 2002.