Our hair colour is determined by varying amounts of melanin, the pigment type, the density and distribution of the pigment granules. Different types of melanin, and the ratio of these pigments produces different hair colours. The mixture varies not only from one person to another, but also across one person’s body. Although people with dark hair may still produce the yellow-orange pheomelanin, it is largely masked by the dark eumelanin pigment and cannot easily be seen. However, the red-yellow pheomelanin is believed to cause the warm, golden, or auburn tones found in some types of brown hair. The range of colours produced by melanin is limited to shades of yellow, brown, red, and black. Grey hairs contain only a few melanin granules, spread out through the hair. White hairs contain no melanin at all. The whiter the skin colour and the more dark pigment there is, so the darker the hair colour the higher efficacy of LHR treatment. The less pigment in the skin and the more darker pigment in the hair, the better result.   Much like the difference in the heating of a car in sunlight, the darker car is hotter at the end of the day than the white car. This principle also holds true for laser hair removal.