Dietary Supplement Sourcing – How To Guide
Purpose: To provide clear, practical guidance for sourcing materials and services used in dietary supplements
in a manner that supports regulatory compliance, product quality, and fitness for intended use.
If you remember nothing else:
- Grams on the label ≠ potency
- % potency defines how much active is inside the grams
- Physical attributes affect manufacturability
- Suppliers are qualified for intended use, not price alone
1. Regulatory & Quality Expectations
Dietary supplement sourcing must comply with 21 CFR Part 111 and applicable food safety
requirements. FDA expects companies to demonstrate that suppliers are capable of consistently providing
materials that meet specifications and support the labeled product throughout shelf life.
Suppliers are qualified based on fitness for intended use, meaning:
- The material meets chemical specifications
- The material performs as required in manufacturing
- The material supports label claim through shelf life
2. Core Concepts Sourcing Must Understand
2.1 Label Quantity vs Potency (Critical Concept)
- Label quantity (grams, mg, mcg): Total material filled per serving
- Potency (% or strength): Amount of active component within that material
Meeting label weight does not automatically mean meeting label claim.
Practical Example
- Label: Ingredient X – 500 mg per serving
- Supplier potency: 10% active
Result:
- Total weight = 500 mg
- Active provided = 50 mg
If the label claim is 50 mg active → compliant
If the label claim is 500 mg active → non-compliant
2.2 Why Potency Is Expressed as a Percentage
- Many ingredients are standardized extracts or blends
- Natural materials vary inherently
- % potency defines active per unit weight
Potency percentage determines how much material must be filled to meet label claim.
2.3 Overages & Shelf-Life
- Potency may degrade over time
- Overages may be required to meet label claim at end of shelf life
- Overages must be scientifically justified and controlled
3. Critical Physical & Functional Attributes
In addition to chemical specifications, sourcing must consider physical attributes that affect
manufacturing and product quality.
| Attribute |
Why It Matters |
| Flowability |
Affects blending, hopper discharge, weight consistency, and segregation |
| Compressibility / Compactability |
Critical for tablet hardness, friability, and avoiding capping or lamination |
| Hygroscopicity |
Impacts stability, flow, microbial risk, and storage requirements |
| Particle Size Distribution |
Affects blending uniformity, dissolution, and content uniformity |
| Bulk & Tapped Density |
Impacts capsule fill accuracy and tablet size |
4. Dosage Form Awareness
| Dosage Form |
Most Critical Attributes |
| Tablets |
Flowability, compressibility, potency, PSD |
| Capsules |
Bulk density, flowability, hygroscopicity |
| Powders |
Flowability, segregation risk, moisture sensitivity |
| Liquids |
Potency, solubility, stability |
5. Sourcing Process – Step by Step
- Define material or service and intended use
- Identify potential suppliers
- Perform sourcing risk review (pre-selection)
- Determine risk classification
- Conduct supplier qualification
- Obtain Quality approval
- Release supplier for use
6. When Sourcing Must Escalate to Quality
- Potency expressed as % or range
- Botanical or naturally variable materials
- Hygroscopic or unstable ingredients
- Overages required to meet label claim
- New supplier or manufacturing site
7. Records & Documentation
- Sourcing & qualification checklist
- Risk assessments
- Supplier specifications and COAs
- Audit reports or evaluations
- Quality approvals
All records must be retained per record retention requirements.
End of Document