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The full narration of the video.
Barely a teenager, and there are already white hairs. Isn't white hair supposed to come with old age? Here's the odd part: hair has no color of its own. Its color gets added down at the root. At the root of every hair lives a little crew of color-making cells. As the hair grows out, they keep stuffing color into it.
Lots of color, and the hair is dark. A little, and it's light. None at all, and it grows out white. Those cells wear out over time. So next to the root sits a tiny storeroom, full of spares. Hair falls out and grows back. Each time a new one starts, the storeroom sends a fresh batch down to keep coloring.
When the storeroom runs empty, new hairs come in white. Mix white hairs into dark ones, and from a distance it looks gray. So why do some people go white so young? Reason number one: it comes from your parents. When the storeroom starts running low is largely written in your genes. Among people who gray early, about two in five have family members who did too.
Reason two: the body is missing something, or something's a bit off. Like too little vitamin B12, or a thyroid problem. With this kind, once the missing piece is added back or the problem is treated, some people's white hair can even turn dark again. Reason three: smoking. One study found smokers were about two and a half times as likely to gray early.
And stress. Scientists saw this in mice. When scared, nerves make the storeroom's spare cells all rush out at once and get used up. Within weeks, black fur turned white. Early graying isn't rare. One hospital in India checked over five hundred young people, and about one in four had it. There's an old saying: pull one white hair and ten grow back. Not true. Each root runs on its own, so pulling one doesn't touch its neighbors.
But keep pulling the same one, and the root can get damaged and may stop growing hair at all. So graying early usually isn't something you did wrong. For most people, their built-in timetable just runs a little early. If a child suddenly gets lots of white hair, see a doctor and check whether something's missing.
Is there something about your body you can't figure out? Leave it in the comments. Maybe we'll explain it next.
Hair has no color of its own. A little crew of cells at the root adds it. When those cells run out, the hair grows in white.
The color they add is called melanin.
“Gray” hair is really dark and white hairs mixed together. From a distance, it looks gray.
That’s why people go white as they age. Some people’s storerooms just empty early.
It’s not rare. For people of Asian descent, white hair before 25 counts as early (the cutoff is about 20 for white people and 30 for Black people). One hospital in India checked over 500 young people, and about one in four had it.
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