wrinkles on my forehead and gray hairs on my head

I am getting OLD! I know this because the wrinkles I noticed on my forehead a few years ago are steadily getting more ... wrinkly. And my gray hairs are multiplying like rabbits. Seriously, rabbits. Really horny gray rabbits are growing out of my head. (Now there's a sentence I never thought I'd type.)

Now let me ask you this question. Is it ever in good taste to tell someone they've got gray hairs? I mean, I'd say that maybe to a very close relative or something. MAYBE. But don't you think it would be kind of rude if, oh, I don't know, a coworker said that to you? Like, they were talking to you, and suddenly paused, looking at your head, and said, "Hey, do you have gray hairs?" Yeah, well, that happened to me. That happened to me in a meeting at work with a bunch of customers from abroad. I believe I handled it appropriately by saying quite cheerfully, "Yes, I do. Thanks for noticing." The perpetrater was a bit embarrassed. As he should be.