My first thought when a kitty's behavior changes is always to see the vet.
Is she maintaining her weight or losing? If you're not certain, and can't weigh her at home, that alone would get me to the vet so you can keep tabs on her weight. Is she showing any signs of being thirsty/drinking more than before? Weight loss, increased appetite, increased thirst, can all be symptoms of hyperthyroidism or diabetes.
Most definitely don't put paper clips or anything else that she shouldn't ingest in her food! An obstruction could end up costing you a *lot* of money, if not worse.
Assuming nothing is going on, you could make her work for her food to slow her down. One of my kitties loved to chase kibble that I'd skitter across the floor a piece at a time.
But personally, I would first want to know what's causing the increase in appetite.