Do you use a business account for your food pics, or just a regular one? 
Just a regular one, should I switch to a business account?
Do you use Instagram for business, or are your food pics just for fun?
My food pics are just for fun, for now.
Do you use Instagram stories as well to post videos or photos of food? I've heard that can help you reach more people.
Yes, I use the stories very frequently. I post about my food about once a week.
I've heard that the biggest thing to growing a following on Instagram is to post regularly, and to keep posting at the same pace. Do you post regular posts at a certain rate?
Yes, I have started to post more regularly, but I take breaks occasionally. 
There are actually ways that you can post automatically, without even logging in every time. There are programs like SocialCaptain, SocialUpgrade, and others that will automate that for you.
Wow! That's crazy, are those applications you can buy to use??