Sensitive skin; a mysterious problem
Sensitive skin is the scourge of many people; many products will be for sensitive skin, and other products will aggravate sensitive skin. But what exactly is sensitive skin? The biggest issue when it comes to sensitive skin is the loss of the barrier function. The main function of the skin is to form a barrier protecting the body against external attacks. So when this function is lost, or impaired, the skin starts to act like a poor sieve; letting through most things. And some of these "things" will be compounds which can potentially cause an irritation or allergy. Another issue when the skin loses its barrier function is that moisture is lost leading to dryness.
Sensitive skin; the nerve theory
Another theory which can explain why some people's skin is more sensitive than others is over-supply of nerve endings. Like all body organs (remember skin is an organ just like the heart, brain..etc) the skin enjoys a supply of nerves which carry messages back to the central nervous system. However, when there is an oversupply of these nerves, the skin becomes extremely sensitive. So you combine a skin with poor barrier function, and a rich nerve supply; and you can see how this can lead to extreme sensitivity to the slightest stimulation. The final blow to sensitive skin is the inflammation that results. The skin has access to the body's immune system to call upon if it comes across what it suspects to be foreign invasion. So when the skin comes into contact with something it doesn't like, it presses the alarm button and calls upon the body's defense to help it. So blood supply to the site increases to bring in more immune cells, therefore skin may become noticeably red. A molecule called histamine is released which act as a signal for more immune cells to rush to the site, and a side effect, this histamine causes itchiness. Which is why skin itches like crazy when you're having a reaction to something. Desquamation may also occur, which is shedding of skin layers. Almost certainly, genetics plays a role but there is no full understanding how this comes about yet. Cosmetic companies have known some of the issues with sensitive skin for a long time, and some products now contain compounds to "calm down" skin sensitivity. An example is a compound called Hydroxylyresol comes from Olives, and it helps by repairing damaged skin cells. Perhaps the "alpha male" of all skin compounds is Hyalluronic acid. It is an amazing molecule which protects the skin against dryness, cell damage and inflammation. I mention it here in one of my earlier blogs. Till next time;