Hair growth/non growth

[blackfive]

Why is it that (from a male perspective), the hair on your head grows fairly quickly, the hair on your face seems to grow even more quickly but the hair on your arms/legs etc never seem to grow at all?

[Hippy]

I have long hair on my head and have had for many years, and it seems to me that it is somehow programmed to be a certain length and no more. I think this goes for the rest of the hair, that is automatically limited to a certain.

Last time I had very short hair was in 1980, and I have grown it long ever since. It reached a just below shoulder blades length in about 18 months, I think, but has not grown longer than that. Although I have a beard, I have never let it grow to its ultimate length. I suspect the ZZ Top men are a guide to what is possible. I have never trimmed or needed to trim my eyebrows. They stay the same size. However, I do have some alarming out of control hairs. One comes out of my left nostril and the other from inside my right ear. They both seem to grow very fast and if left just keep on and on. They have the consistency of fuse wire and tickle like mad.

[xyzzy@bok]

it's 'simply' due to genetic instructions for length e.g. pubic and underarm hair grows a certain length and then stops. Now if they could genetically modify grass seed this way we wouldn't need lawnmowers :-)

[robber1]

Or maybe turf our heads!