Why are bald heads so shiny, when the skin elsewhere on your body isn't?
It's all because of the vellus hairs and sebaceous glands.
Asked by: Dave Jefferies, Barrow-In-Furness
Most of the skin on your body is actually covered with tiny hairs called vellus hairs that give your skin a slightly velvety, peach-fuzz look. With male pattern baldness, the hair follicles shrink and turn into skin cells, so there are no hairs at all – not even vellus hairs.
But the scalp is particularly shiny because of the sebaceous glands. These secrete oil and are found all over our skin, but the scalp has a lot more and this oil coats the skin and provides a more uniform reflective surface. What’s more, studies suggest that more active sebaceous glands could actually play a role in early hair loss.
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Luis trained as a zoologist, but now works as a science and technology educator. In his spare time he builds 3D-printed robots, in the hope that he will be spared when the revolution inevitably comes.
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