How Hair Grows
Q: I just want to know from where the hair's growth starts, from the top or from the bottom?
The follicles generate hair cells in long strands and as these strands get longer and longer they are pushed out of the follicle and emerge above the surface of the skin. Because of the way the hair grows the portions of the hair that are furthest from the scalp are - of course - the oldest.
In fact, if you measure the length of the hair and divide the it by one-half inch (or 2.5 cm) the resulting number would be the approximate age of the hair at the ends of the strands in months.
This is why most damage to the hair shows up at the ends of the hair first. It is older, and has been exposed to styling stresses and environmental damage longer than the rest of the hair closer in to the scalp.
Photo: Olena Zaskochenko/Shutterstock
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