Science Nature Beauty

Explaining sensitive skin and how to deal with it

50% of all people perceive their skin to be sensitive. Their skin is hyperreactive and shows a strong reaction to even the smallest stress. Skin gets itchy, or experience burning or stinging sensations on their skin. Common triggers of skin reactions in sensitive skin are make-up, fragrance oils and preservatives in cosmetic products.

Sensitive vs. irritated vs. allergic skin

Sensitive skin is hyperreactive. It gets irritated easily. Even the smallest stress can lead to big problems. There is something ‘wrong’ in the skin which makes it hyperreactive. This is different from skin showing an irritation after having been exposed to quite a large stress. In these cases, your immune system reacts to that stress and is trying to deal with the problem caused in the skin by this stress. This immunological process can be accompanied by visible signs of irritation, like redness and bumps. Often, this process also includes sensations like itch or pain, quite similar to what we see with people with sensitive skin. In the case of irritated skin, though, your immune system reacts normally. It is trying to solve the problem and with the accompanying signs it is essentially telling you ‘I am at work and solving your problem’. Our immune system is even smarter than that. For instance, if you stay out in the sun too long and your skin gets burnt, you feel it. Essentially, your immune system is not just trying to solve your problem, it is even saying ‘get out of the sun’.

Many people suffer from allergies. Here too the immune system is reacting to something and, analogous to the processes taking place in sensitive skin, the immune system is overreacting. There is a large difference between sensitive and allergic skin though. The origin of this difference lies in the fact that our immune system essentially exists of two parts. One part of the immune system is unspecific. This part is called the innate immune system. The other part is specific, this is called the adaptive immune system. In case of skin allergies, there is something wrong with the adaptive immune system. This system, which supposed to be very effective and goal-oriented in reacting to known stresses (i.e. allergens), has developed such a reaction to a substance which is normally not dangerous to our skin, our body. This is where the adaptive immune system reacts quickly and harshly, leading to an allergic reaction. An important biological feature is part of this reaction, histamine is released locally in the skin leading to strong itch, redness and bumps.

top

In search of a solution for sensitive skin

Sensitive skin has long been underestimated by scientists. It was not understood, biologically, and it was largely seen as a subjective problem with a large role for the psyche. The fact that sensitive skin reactions, more often than not, are not accompanied by visibly signs of irritation, like redness, did not help in convincing these scientists to look more closely into this topic. Luckily, it is now taken much more seriously and we now know much more about sensitive skin than in the past.

In sensitive skin the adaptive immune system, which is the main player in allergic reactions, only plays a minor role. It is the innate, unspecific immune system in our skin which leads to these irritating and rather random reactions in sensitive skin. Many other factors play a role. Some of these are heavily debated, but we can already conclude: Allergic reactions are, biologically, specific and scientifically comprehensible. Skin irritations (e.g. after having been in the sun too long) are, in essence, sensible and normal. Sensitive skin, however, is more complex, biologically.

That begs a few questions. How do we need to deal with sensitive skin? Where to start? We need to start with the realization that the immune system is a very hierarchic system. A vast network of immune cells is working, reacting and communicating to problems and in sensitive skin they are working, reacting and communicating too much. Most of the times, though, these processes start with the skin cells, the cells in the outer part of our skin. These cells, keratinocytes, are the first cells to react to a problem. As a consequence of that all the other cells are activated. From a hierarchic perspective, therefore, our keratinocytes stand at the top. Nerve cells are other cells which are important in the context of sensitive skin. Irritations always involve nerve cells and these cells are in very close contact with our keratinocytes.

top

Hierarchy in cell-cell communication

As mentioned above, cells react and communicate. These processes work through molecules. One cell produces a molecule, this molecule is sensed by another cell and this cell reacts to that by for instance, starting to communicate to other cells by also producing this molecule. This can lead to a ‘snowball effect’, leading to a strong amplification of the production of this molecule. These molecules can be proteins, lipids, hormones and can play different roles, positive and negative. The net result of the production of all these molecules can be inflammation, irritation.

The communication through molecules is very interesting. Different molecules play different roles. Where one molecule induces processes, which lead to the skin becoming red, another molecule will trigger itch. These molecules play different roles and are part of different biological systems. One system leads to redness, the other to itch. These biological systems include these molecules and specialized cells leading to their different outcomes.

Analogous to the cells acting in our immune system, there is also a hierarchy in these biological systems. A biological system which is high in the hierarchy can activate or deactivate a biological system which is lower in the hierarchy. Back to the above conclusion we drew about sensitive skin: it is biologically unspecific and complex. If we want to have a significant positive effect on sensitive skin, we need to act on the main players, those cells and biological systems which are highest in the hierarchy. If we can positively influence them, we will also influence any process and cell which are lower in the hierarchy.

Keratinocytes and nerve cells are the cells to focus on, but what is the biological system we want to work on to make sensitive less reactive and more comfortable? After years of research, our labs found it. This system is called the endovanilloid/endocannabinoid system. This sounds complex and it is, but the essence is simple. In the endovanilloid system, cells and molecules co-operate to induce strong inflammations. Whatever inflammation you have in your body, the endovanilloid system is always prominently present, activating systems lower in the biological hierarchy to induce problems like pain, redness or itch. Its counterpart is called the endocannabinoid system. This system is the key system with which our body tries to maintain health. The endocannabinoid system compensates for and fights against the endovanilloid system. Both systems are heavily intertwined, so we are actually talking about 2 systems in 1: the endovanilloid/endocannabinoid system.

top

Effective care for sensitive skin

Effective care for sensitive skin, making the skin less sensitive, should address our skin cells, the keratinocytes, the nerve cells and the endovanilloid/endocannabinoid system. This approach makes sure that we act on all important biological aspects of sensitive skin, all highest in the biological hierarchy. This is what we did with our product AnnonaSense CLR™. Our cell biological studies showed incredibly strong effects and these were confirmed in our clinical studies. Skin becomes less sensitive, skin looks and feels better. Skin is less blotchy and itch is reduced. Importantly, the volunteers in our study reported that they felt better after using a formulation with AnnonaSense CLR™. Their well-being and quality of life was improved.

top

Author

Harald van der Hoeven

Director Product Design & Development