There is a very good chance that the website you referenced is using a custom-coded solution. If you are looking for something specific, I would recommend looking for a developer to hire as well. Feel free to check out our Shopify experts directory. With that said, there is an app called MWP Diet Calorie Calculator that might suit your needs. It's $15.99/mo and comes with a free trial. They have an app demo you can check out for free here to see the app in action.
If there is anything else I can help you with, please let me know.