Can I eat anything I want if I run?

Hello! I am thinking of buying a treadmill - I can't run outside - and I was wondering if I could eat any foo d I wanted if I ran 20-30 minutes a day and walked an hour. I might eat some junk on occasion, but mostly I eat pretty healthy food. I have heard people say "Don't run, you'll just end up eating as much as you burned, because running makes you hungry." Is that true? I asked my mother and she said not really. Thanks! :)