The Yeast on our Scalp

Here is a riddle: what is flaky, white, and appears in more abundance on some people than others? If you answered “dandruff”, you are correct! These flaky annoyances usually make their first appearance in a person’s hair during puberty and form due to different reasons. One common reason for the formation or increase in dandruff is dry skin; as winter approaches and the temperature starts to drop, the skin on your scalp may start to dry, causing more dandruff to form. Another reason could be due to the presence of a type of yeast on your scalp. Your scalp is home to an abundance of microorganisms, one of which being malassezia, a lipophilic yeast that naturally lives on the scalp of many people. The formation of dandruff begins when these yeasts start feeding on an oily substance produced by the sebaceous glands on our scalp. This oily substance is called sebum and consists of a mixture of fatty acids, triglycerides, wax esters, and squalene. By consuming and breaking down the sebum on our scalp, these microorganisms produce oleic acid as a byproduct, irritating the scalp of people with sensitive skin. This irritation causes the skin cells on the scalp to regenerate at a much faster rate, leading to the formation of flakes (dandruff) as the dead skin cells build up.