Grey hair mystery?

My hair have been gradually turning grey since I was 16. I would say now about 20% of my hair, particularly on my right side are grey. Recently my doctor also found that I have an enlarged nodule on my thyroid. This nodule is slightly hyperactive (I am not losing any weight) but other than that my thyroid is under control and I am not taking any meds.

I have been coloring/highlighting my hair except for the past 9 mos. I have been letting them grow naturally.

I have noticed that some of my hair are banded (dark pigment banded with much lighter/greying pigment) Kinda like cat's hair.

I also found a couple of hairs that are grey at the tips!!! not the roots. The roots are black.In fact, most of those hairs are black except the tips.

Now I am not sure if some of my grey hair are turning black again, or are they greying at tips instead of roots???

I had much stress last year but I am much better now. Again, I am taking no meds of any kind.

Any clues?

Grey hair mystery?

the only clue I have is one that my husband has. He was very gray at the age of 19, and now almost all gray with a little pepper. This is indicative of osteoporosis. This is rarely stated in articles on osteo. His brother has it also. Best wishes. By the way I think his hair is very sexy.