Skin color is due to many things. One is the content of the pigment. Most important is called as melanin melanin is produced by cells called as melanocytes. Most of the people if they are white or dark in colour, they have same number of melanocytes but the production of melanin is more in the dark and les in the light. Melanin is of two types. One is reddish colour melanin and the other is brownish colour melanin. Reddish colour melanin gives rise to red head or red haired people, in fair people , the Caucassians. Browninsh color melanin is present in most of us. When the brownish colour is melanin is produced in very large quantities, it starts looking black in color, another thing responsible for the colour of the skin is called a s hemoglobin. Hemoglobin is present in the blood. That gives a pinkish tinge to the skin. So people who have anemia, even though they have melanin, they look very pale. Melanin is protective pigment and protects us from harmful radiation from outside. Melanin acts as a UV filter. So Melanin is a natural sunscreen. So it protects he harmful UV light from entering inside the body and causing mutations and cancer, so when we do any skin lightening treatment, we have to explain, that it is not good thing and it will make your skin sensitive to sunlight for those people who have no choice and is in an industry that requires them to be fair w e go ahead with some skin lightening treatment. If it is for the entire body, there is an injection called as glutathione , along with Vitamin C at weekly intervals this causes lightening of the skin by 2 to 3 tones, this is more effective in people who are darker and less effective in people who are lighter. Glutathione changes the brownish colour melanin to red colour melanin. Therefore the brownish colour becomes light brown color and it improves skin tone. Vitamin C also improves the skin color, so we give it along with the glutathione. If it is only for particular body areas, we do Gluwhite tablets or we do vitamin c.