Are there any restricted items like food when you enter the airport?

Normally they focus on liquids. I have been able to keep my snacks that were in my backpack a few times. Pretzels etc. Not sure if this was oversight on anyone's part but happy it saved me from overpriced airport stores.

Yes There is a restriction

You can bring your food stuffs through TSA so long as there are no liquids in containers which hold more than 3 oz.

No Only When You Go Through TSA.

I don't think so