1. Chemical solutions (creams, lotions etc), designed to improve the outer appearance of skin. Very few customers know that the water and fat molecules can barely penetrate the skin (which is the reason why our skin doesn’t disintegrate when we’re swimming in the sea or when it is covered by something). The skin is our protective suit for use in our surroundings. Skin is penetrated by certain types of acids, not damaging it, but that means they don’t rejuvenate it either.
2. Injection-based approaches that are favoured by many cosmetologists. This method allows to penetrate the epidermis (the outer layer of skin) but when the chemical or biological solutions get under the skin, they are dissolved in blood. It’s the second line of defence of the human body. All molecules that weren’t in their “places” and came into the body from outside are dissolved by blood and eliminated in the liver. That’s why localised injections lose their effect very quickly and have to be repeated for them to have any considerable effect.
3. Some approaches favour causing micro injuries, which create localised inflammations at points of injury. The reasoning for these methods is that stem cells of the skin are expected to displace old and dead ones. This might be true but only for a time, as the aftermath of this approach imitates new skin but the reality of it is that the patient doesn’t know that old skin barely contains any stem cells and the “offsprings” are also created by an old skin and hence there’s no real rejuvenation. It also has to be considered that if the “new skin” is to be subjected to micro traumas repeatedly, then keloid scars will start to appear as a result and keloid scars are irreversible.