My husband swears that this is true (probably based on the fact that his did; however, I feel that his is just a bad tattoo!) I completely disagree. If this were the case, no one would ever get a single tattoo, let alone entire sleeves, etc. What’s the real deal on tattoo aging?
Cheap ink and UV exposure are the main reasons a black tattoo will fade to that blue/green shade.
People aren’t thinking of the future when getting tattoos.
Yes, tattoos do tend to go bluish-green. Sun exposure speeds the process up.
My 33 year old tattoo is still black, it’s just spread out enought to be hardly recongnizable. It’s on my left forearm and gets lots of sun.
Cite?
I think you should read this thread.
They don’t all fade, the yellow and orange in mine disappeared altogether.
People aren’t thinking of the future when they wear t-shirts, the whole point of a tattoo is that it lasts into the future. 
Anyway this is IMHO stuff.
Got my first tattoo in 1977. The black is still black, but the yellow is gone and the red has faded some.
My tattoo(s) are all beyond 20+ years old. I took care to use sunscreen [most] of the time. The black is still black, the reds are still red, the yellows are still yellow and the blue is still blue. Nothing has morphed into another color.
Everything has kept it’s color well and not faded except one: the gray on a characters hat has faded so much it’s hardly there. While it’s still apparent that it’s a cowboy hat, only the outskirts of it appear gray. The rest of the hat is the color of my flesh.
I’d just wanted to chime in to say that I do. I have a sunscreen in a chapstick like applicator that I use on the tattoo on my forearm for just this reason.
I dimly remember my tattooist telling me the old blue tattoos you see are the result of the type of ink they used to use back then, and modern tats will just fade (the degree of fading depends on color and sunlight exposure). They might also blur or warp slightly depending on body location as your skin changes shape. This was a long time ago and I may be remembering it wrong, so take it with a grain of salt.
Do you retouch tats?
My tattoo is around 5 years old, but since it is under my shirt, it rarely sees the sun. Its still black and pretty good. I did hear that colored tattoos are more likely to fade over time, as many others have pointed out above.
I wouldn’t mind having a blue tattoo too, I would still like mine.
You certainly can get them touched up to re-vitalize the color if it has faded. I intend to get mine touched up sometime soon to darken them back down. My black work is eleven years old and has gone dark gray compared to the new black.
All tattoos definitely do not turn blue. If you keep them protected from the sun and they were done well (ink not put in too deep nor too shallow) they should not fade significantly. My oldest tattoo is about 12 years old now and still looks great; it has green, red, black, blue, and purple. I have had some of mine touched up a couple of times, but it was more due to not being satisfied with it originally, not due to fading.
What about the ink used for permanent makeup such as eyebrows? Is that really different from tattoo ink?
That was my understanding too. I remember asking my tattooist about it, but she must’ve determined I was being a worrywort and didn’t answer.
Definitely. I’ve had my back touched up a while back, and will probably do so again within the next few years. The Black and Grey piece on my arm that I got in '97 still looks great, but my back has a ton of color in it, especially red and yellows, which tend to fade faster than most other colors.
My tattoo is white ink, supposedly it will turn yellow-ish (which I’m ok with) and possibly fade away entirely. No blue here.