general question about hair growth

I’m a 20 year old caucasian male, average “hairiness.” I have some extremely fine, blond hairs on my shoulders and upper arms (bicep area) that are more or less invisible, except when i look for them specifically. They range from very short to maybe 1/2" long, but all of them are very fine and light, hardly noticeable. My question is this: will these hairs inevitably turn into dark black hairs one day, or is it possible that they will always stay just the way they are?

Thanks for the info!

No, it is not inevitable that these fine, light hairs on your upper arms and back will become dark and coarse someday. What do your older male relatives look like in these areas? That might give you a hint, but doesn’t necessarily mean that you will follow their hair patterns.

Usually, in males 35 or older, the body pattern of hair will not increase that much. What they have at age 35 is probably going to stay stable. Young men have more accelerating hairs because the hair patterns are in the development stage from puberty to age thirty to thirty-five.

As a twenty year old, if you start to see a great number of fine hairs turning to dark, coarse hairs, then your patterns are still developing and will most likely continue developing for the next ten years or so.

What you see now, very well could stay that way the rest of your life. You can not know the full potential size or pattern of your hair growth when you are a male and twenty years old.