Dry or excessively oily scalp
Dry scalp loses its natural moisture, causing the cuticle to become brittle and flaky. Dead skin cells build up on the scalp, causing dandruff, itching, and irritation.
The habit of scratching when itchy can damage the scalp, creating an opportunity for bacteria and fungi to grow, making dandruff worse.
Oily scalp secretes excess sebum, creating a suitable environment for Malassezia fungus to grow. When the fungus thrives, it secretes oleic acid, causing skin irritation, peeling, and dandruff formation.
Excess oil clogs pores, preventing dead skin cells from being removed effectively, making dandruff worse.
Malassezia fungus
Dandruff is often associated with the fungus Malassezia because this fungus naturally lives on the scalp of most people.
The scalp produces sebum (a natural oil) to protect and moisturize. Malassezia uses this sebum as a food source. When too much sebum is produced, the Malassezia fungus overgrows, causing an imbalance in the scalp's microflora.
Malassezia breaks down sebum, producing fatty acids (especially oleic acid). These acids can irritate the scalp in some people, causing the scalp to react by flaking more quickly than normal. This flaking is what we see as dandruff.
Using the wrong hair care products
Using the wrong hair care products can cause dandruff because the ingredients in the product or incorrect usage can irritate, unbalance or damage the scalp.
Some products contain harsh chemicals like sulfates (SLS, SLES), parabens, or synthetic fragrances that can irritate or cause an allergic reaction to the scalp. This reaction causes the scalp to flake more, leading to dandruff.
The scalp has a natural pH of 4.5 to 5.5, which helps maintain a healthy barrier and microflora. The wrong products can alter this pH, causing an imbalance that allows the Malassezia fungus to thrive, leading to dandruff.
Stress, poor nutrition
Stress impairs the function of the immune system, making it difficult for the body to control the growth of Malassezia fungus on the scalp. When this fungus overgrows, it causes inflammation, causing the scalp to flake, leading to dandruff.
Stress stimulates the sebaceous glands to become more active, making the scalp more oily. This creates an ideal environment for fungi and bacteria to grow, making dandruff worse.
