I have not imported all the necessary data from the US Food DB into my PostgreSQL server. However, while I was looking into this, I found a DB called OpenFoodFacts. From my quick search, using OpenFoodFacts as my primary DB has certain benefits and drawbacks:

Pros of Using OpenFoodFacts:

• The information is more user-friendly. It has pictures, barcodes, and names of the food item. This is absent in the US Food DB, and why I wanted to use Nutrionix at the beginning
• The data is easier to handle as it's all in long table

Drawbacks of using OpenFoodFacts:

• The data comes from user contributions, allowing for many more mistakes. In fact a lot of the information is different from the US Food DB.
• Lots of data is missing

With these issues, I don't think I will use OpenFoodFacts as my primary DB. However, I might use it near the end of the workflow if I want to provide the user pictures, barcodes and names of the products.