The primary determinant of your skin color is the amount and type of melanin present in your skin. This substance is synthesized in melanocytes, found in the epidermal basal layer. After it’s synthesized, it’s bound to a protein matrix and forms melanosomes. Inside the melanosomes, tyrosinase converts tyrosine into eumelanin or pheomelanin, which are actually skin coloring.
Note: As you can see, there are four different distinct steps to coloring your skin. Skin lighteners block the process at one of the points in the pathway, and thus can inhibit or even reverse the process that colors your skin. Even if your problem is local, skin lighteners can treat hyperpigmentation without fading the skin around the dark spot.
The difference between skin that tans easily and skin that doesn’t is in the melanosomes and melanocytes, cells found in the skin that cause the darkening you see with a suntan. Asian skin has more of these cells, the cells are larger, and the cells possess longer dendrites than those found in Caucasian skin. The color of the melanin itself is also slightly darker. And the outer layer of Asian skin is thinner as well, making the melanosomes and melanocytes more reactive to even a little light. The overall effect is that Asians tan darker, faster, and more thoroughly than Caucasians in the same light.
When a product is advertised as a skin lightener, it primarily inhibits the synthesis of tyrosinase, an enzyme which stimulates melanin production and distribution. Hydroquinone is the most effective lightener known, but it’s also know to cause skin irritation and has several undesirable side effects. Arbutin and harounoside, derivatives of hydroquinone, are promising in their action without so many negative side effects.
Many skin lightening creams have gone to all natural alternatives to hydroquinone, and use extracts of plants like mitracarpe (containing harounoside), bearberry (containing arbutin), and licorice root to effect skin lightening. The advantage to natural ingredients is that they more rarely have negative side effects, and are generally nontoxic and nonirritating. You should also ensure that your skin lightening cream contains some sort of moisturizing ingredient that will not clog your pores.
Prepare your skin for a lightening cream by using a good natural cleanser made for your skin type, followed by an alcohol-free toner. Apply your lightening cream, and then follow by a light moisturizer, especially if you have a lightener with no moisturizer inside it. After lightening, always avoid exposure to the sun and use a sunscreen whenever you need to go outside.