I am new to microdermabrasion and even my esthetician approaches my highly sensitive skin with extreme caution. After hearing about it in conjunction with a glycolic peel, I was determined to learn more.

First a quick digression. I have Lisa Sugar (founder of the popular Sugar network of sites, including the beauty blog BellaSugar) to thank for the term 'esthetician', which, according to Websters , is "a philosopher dedicated to the nature of beauty." So much nicer than 'facialist' or 'dermatologist'. I shall be having monthly visits with Ildi, my personal beauty philosopher, from now on.

Anyway, back to the topic at hand. Crystal microdermabrasion systems are the traditional treatment of choice. Tiny crystals are blasted onto the skin to perform an exfoliating process. Although still widely used, the introduction of alternatives has led to a trend towards diamond microdermabrasion systems. The diamond tipped head makes contact with the skin and abrades against it. I have had the latter.

Aluminum-oxide crystals (which are the industry standard) require a mask and protective eyewear to avoid loose crystals entering through the eyes, nose, or ears. In contrast, the advantages of diamond are shortened procedure time and less of a mess. Patients have commented that the crystal-free procedure is usually much less painful while not sacrificing results.

Want to know how it works? Your skin is made up of two main layers, the epidermis and the dermis. The epidermis is the top layer. It's a set of dead skin cells on top of another layer of cells that are in the process of maturing. The topmost layer is called the stratum corneum. It acts as a barrier between the outside world and the lower skin layers. The idea is that if you remove or break up the stratum corneum, the body interprets that as a mild injury and rushes to replace the lost skin cells with new and healthy ones. Also, without the stratum corneum acting as a barrier, creams and lotions are more effective because more of their active ingredients and moisture can find their way down to the lower layers of skin.

It's entirely painless. You'll feel a mild suction. The vacuum action of the machine has four main functions: It pulls and raises a small section of skin to work on; creates mild swelling (not really visible) and brings some of the impurities to the surface; in the case of crystal, it shoots a stream of crystals across the targeted skin patch; it collects the used crystals and dead skin.

Wikipedia claims that there is very little, if any, evidence that microdermabrasion stimulates collagen formation. This seems to be a bit too much of a sweeping statement. There are a number of studies that suggest otherwise, such as the one published in Esthetic Surgery Journal in 2004: "Dermal thickness was increased by as much as 40% in the thinner skin and by 27% in the thicker skin. Similarly, the increase in collagen-bundle thickness was 22%, whereas the increase in the epidermal thickness was 9%. Conclusions: The findings of this preliminary study appear to indicate that microdermabrasion produces real increases in dermal thickness, collagen-bundle thickness, and epidermal thickness." A 2005 study published in the Journal of the American Academy of Dermatology implies that more than one session is required to have any effect on skin thickness.

Whilst researching this, I stumbled across Joanna, a 35 year-old stay-at-home mom who is obsessive about microdermabasion and has a whole website called skinabrasion.net devoted to her experiences.