The bulk of dust in your house is dead skin from the people who live in it. The skin is continually renewing itself from below and part of this process is the shedding of dead cells. This creates a lot of dusting. As always seems to be the case with the skin, looking into the details of the process. The bottom layer of the skin is the junction of the dermis with the epidermis. Cells from the dermis migrate upwards, losing their fluids and becoming more squashed as they get nearer to the surface.

When they get to the top layer, the stratum corneum, they have become flattened and dried out and are now composed mainly of protein. They are now known as corneocytes. I can remember being taught that corneocytes were lost simply by them falling off. Once they corneocytes have got to this stage of being ready to be lost, they are known as squames. The process by which they are lost is known as desquamation. It is now known that this process is controlled by enzymes. The main enzyme involved is one of my favourites. It is called stratum corneum chymotryptic enzyme, or SCCE for short. The corneocytes are held together by tiny sttrands of protein called desomosomes. The role of SCCE is to snip these strands allowing the corneoctyes to desquame.

Enzymes have some common characteristics. They tend to work well when there is plenty of water about, and they have an optimum temperature and pH. There are a lot of biochemical processes going on in the skin, and our fried SCCE is just one of them, but nonetheless a crucial one. The rate at which skin cells are lost must be a pretty key one to keeping the skin in tip top condition.

Which brings us to exfoliation. A lot of people use scrubs to remove the top layer of their skin and reveal the younger looking skin beneath. That is the theory at any rate, and a lot of people regard this as part of their regular regime to keep their skin looking good. I have to say though, that I am beginning to wonder if this is in fact the best approach. Surely moisturising the skin and avoiding anything that is likely to interfere with the skin’s collection of enzymes should work better?

This is a scientific blog, and science is all about testing theories. I plan to find a good exfoliator and a good moisturiser and use them on either side of my face to see if we can see any difference between them. But if anyone else has any experience in this area I would love to hear from them.