Regardless of the accuracy of the data from your suppliers, you are still legally required to report accurate nutrition analysis data on your Supplement Facts panels or other reports.
Due diligence is the process you use to ensure that your data is the most accurate it can be. Using Genesis R&D lets you simplify the process.
The Dietary Supplement Labeling Guide is the FDA's guidance document for regulatory information on the labeling of supplements. Refer to it when you have questions.