Dandruff is an extremely vexing problem for many young adults. The annoying part is not in the dandruff treatment per se, but in the fact that dandruff comes right back as soon as the treatment is stopped. To prevent dandruff from coming back, it is imperative to understand the basic causes of dandruff.
Causes
Dandruff is caused due to three main factors - Malassezia fungi, sebum secretion on the scalp and individual susceptibility.
1. Malassezia fungi
The main causative agent implicated in dandruff is a type of fungus called Malassezia. There are several species of Malassezia identified and few of them are part of the normal “commensals” of the skin surface. Commensals refer to the organisms that reside on our skin without causing any disease and help in maintaining the skin balance. Then why does this commensal start producing dandruff? This is explained by the other two factors.
2. Sebum secretion
Our skin on the scalp, face and upper trunk has a high density of oil glands. During adolescence, these glands become bigger and active under hormonal influence. They continue to remain active throughout adulthood with peak between 20-40 years. Malassezia organisms secrete enzymes that convert the triglycerides present in the sebum to irritating free fatty acids that cause scalp inflammation. This causes the symptoms of dandruff like itching, flaking and greasy scales on the scalp. But why does dandruff affect only few individuals and not everyone? This can be explained by the third factor.
3. Individual susceptibility
Though not completely understood, genetics and a specific immune deficiency against Malassezia make certain individuals more prone for dandruff. These individuals have a defective skin barrier that can allow the fungi enter the deeper part of the scalp to break down the sebum releasing the irritating by products, thus causing dandruff. Individual susceptibility is also the reason that dandruff comes back after stopping dandruff treatment.
Dandruff and related problems
Dandruff symptoms include itchy scalp, oily scalp, greasy scaling that could be mild or severe enough to fall onto the clothes.
Dandruff and hair fall
Dandruff and hair fall can be related. Since dandruff causes scalp inflammation, it can worsen androgenetic alopecia (Hereditary baldness). Dandruff, however, does not cause baldness per se and is only known to worsen male and female patterned baldness.
Dandruff and pimples
Dandruff and acne can be related as both have Malassezia fungi as an implicated agent. Thus, the popular belief that dandruff causes pimples can be true to some extent as this organism is implicated in a type of acne called P.folliculitis in young adults.
Dandruff and psoriasis
Dandruff occurring nearer to the hair line and also as well-defined patches could be scalp psoriasis. Dandruff and psoriasis can also co-exist in the same individual and is called as seboposriasis.
Dandruff Treatment
Dandruff can be treated effectively by 2% ketoconazole and zinc pyrithione containing shampoos. Ketoconazole, an anti-fungal, acts against Malassezia fungi and also has anti-inflammatory property. It thus provides relief from itching and scaling. It has to be used twice a week in the initial phase of treatment and thereafter maintained with weekly applications to prevent dandruff build-up.
There is no difference between dandruff shampoos for men and women. This may just be a marketing gimmick to target both the genders.
A lot of home remedies for dandruff have been recommended. Lemon juice, onion juice, curry leaves and coconut oil are a few popular ingredients that are used for treatment of dandruff at home. These too, however, cannot stop dandruff from coming back.
Hair oils of different types like coconut oil, olive oil, almond oil and our age-old ayurvedic oils are very popular to control dandruff. But what you must remember is that Malassezia fungi is “lipophilic”, i.e. they are attracted to oil and thrive well in an oily mileu. Hence, do not leave hair oil overnight if you suffer from dandruff. Oiling your hair for just half an hour to an hour prior to shampooing is a good practice if you have dandruff.
In my personal experience as a dermatologist in Kochi, majority of patients use oil as a treatment for dandruff. This is not advisable.
Prevention
Dandruff cannot be permanently cured. It can only be prevented from coming back by continuing to use anti-dandruff shampoos containing 2% ketoconazole once a week. This simple regime is enough to ensure that your scalp remains dandruff free. Dandruff can continue to linger as long as the sebum production on the scalp continues, sometimes into the fourth decade. Weekly usage of anti - dandruff shampoos is safe and has not shown to cause any adverse reactions.
Dandruff can also mimic other scalp conditions like tinea capitis, psoriasis, atopic dermatitis and contact dermatitis. Hence, if conventional dandruff treatments are not working, please do get it evaluated by a dermatologist.