OT - riddle me this - question about dark brown eyes

I tried researching this online but I couldn't find much info. I was born with dark brown eyes and have had dark brown eyes until my early 30's...I'm talking so dark brown they look almost black. Within the last 10 years my eye color has been doing something strange (keep in mind that my eye doc sees nothing wrong with my eyes except Dry Eye Syndrome).

So I thought I would pick your guys brains. Now I know that eyes can lighten over time due to genetics. My mother had dark brown eyes and my father had light blue eyes.

So anyway, I haven't been paying much attention to the color of my eyes lately but I just happen to be walking by a mirror earlier and was shocked at how light my eyes have actually become. I now have a wide dark gray/blue/purplish ring around my iris (I've always had lavender on the top ring of my iris but now it encompasses the entire ring). The actual iris is now a hazelly/golden green.

So, knowing that my eyes are healthy, what can cause such a drastic change in eye color??? Has anyone else have anything similar?

www.mayoclinic.org/diseases-conditions/high-blood-cholesterol/expert-answers/arcus-senilis/faq-20058306

It may be arcus senilis which Mayo Clinic says is harmless. But some other sources say this indicates high cholesterol and triglycerides. Does your blood test say you have elevated lipids?

My brother had very dark brown eyes as a kid and now they're more hazel. My daughter has dark brown eyes and both me and my DH have light hazel eyes. I believe my daughter's eyes are actually hazel and not genetically brown, they are just a dark cast of hazel and they will probably lighten as she gets older, like my brother's have.

My brother lives in Steamboat Springs and has been in Colorado for 30 years. He thinks his eyes have lightened because of UV exposure, but he's just guessing. No one in my family has high cholesterol.