My Cat Tyler is an Indoor Cat
(Somerville, MA USA)
I recently (about 4 months ago) adopted an adult male cat we estimate to be about 9 years old. His name is Tyler. His original owner was a woman who worked for an animal shelter and took him in as a stray.
He has had to have some teeth removed along the way (before I got him) and has had a few minor health issues. He know appears to be a normal healthy cat, but I do think he yearns for the "great outdoors."
I live in an urban area, and we now have skunks, raccoons, possums, and I am told larger animals in our area. That combined with cars, sadistic individuals, ect. is the reason I do not let my cat outdoors.
I am told that on average indoor cats live longer than outdoor cats. You would think that lack of exercise would be a problem for a cat's health, but on balance, I feel the dangers outside far outweigh the fact that he gets less exercise being indoors.
My last cat before this (some 30 years ago) was an indoor/outdoor cat, and he managed to survive that. However things were different then, because there were not wild animals around, and in other ways I think it was a safer environment for a cat outdoors.
I think that if you have a totally indoor cat, you must take care not to overfeed him or her, and give the cat the best quality food that you can.
Hope this is helpful to my fellow cat owners out there!