alt Hacker Newsand god help you if those loops are pairing People and Products.
though now that I write that out... it would be really nice if you could optionally type iteration vars so they couldn't be used on other collections / as plain integers. I haven't seen any languages that do that though, aside from it being difficult to do by accident in proof-oriented languages.
You usually don't need an index that can't be used elsewhere. If you don't then you can abstract it away entirely and use an iterator or foreach features.