Notes on Certificate of Analysis, Lab Standards, and Supplement Quality
Certificate of Analysis and Supplement Quality: Key Concepts
CoA limitations and trust issues
We cannot assume the information on a certificate of analysis (CoA) is fully accurate or complete.
ConsumerLab and other organizations have found CoAs to be sometimes inaccurate or bogus.
Key questions a CoA does not fully answer:
Does the product contain the correct materials, or could there be counterfeit or adulterated components?
Are there toxins, pesticides, or heavy metals present?
Does the product meet label claims?
Is the product stable or expired?
Were solvents removed appropriately during extraction? Are active components present?
Conclusion: A CoA does not by itself guarantee quality and purity, even though it would be ideal if we could trust CoAs completely.
Solvents in botanical extraction
Solvents can be liquids or gases used to extract or dissolve chemical constituents from botanicals.
Example: turmeric root; major constituent curcumin is extracted using a solvent.
Common solvents range widely (likely two to 300+ solvents exist); typical benign ones include water or certain alcohols, but many toxic solvents can be used.
Important regulatory point: the FDA does not require testing of solvents in supplement manufacturing.
If a company opts to remove solvents and test for them, that is not mandated by the FDA.
Implication: even an accurate CoA doesn’t ensure solvent residue has been tested or removed.
Evidence from regulatory investigations (value and limitations of CoAs)
2015 New York Attorney General investigation across major retailers (Walmart, GNC, Target, Walgreens):
Samples: 78 samples across NY; Tests: 390 tests conducted.
Finding: 79 ext{%} of DNA tests did not match the labeled herbs (roughly four out of five products).
Examples cited:- A popular ginseng store-brand supposedly for endurance contained only powdered garlic and rice.
Ginkgo biloba product contained powdered radish, house plants, and wheat; label claimed wheat-free but contained wheat.
Canada (2013): 44 products from 12 companies tested; only 2 of 12 companies met label claims; DNA results showed fillers like rice and other plant matter.
Even professional brands are not immune:
Hexavalent chromium (a carcinogenic form of chromium) found in 3/6 chromium supplements tested from professional brands.
3/20 protein powders and sports drinks had mislabeled sugars/carbs.
Lead found in 2/3 products.
Amazon impersonation case (02/2023): NOW Supplements and other brands found products being sold as impersonations of NOW on Amazon.
Impersonation labs located in Spain and Italy; counterfeit products with questionable ingredients were sold.
After discovery, brands pursued litigation; ongoing risk due to Amazon’s scale.
Practical takeaway: buying supplements on Amazon or through unknown retailers increases risk of counterfeit or substandard products; advise clients to avoid Amazon and use trusted channels (e.g., practitioner channels like Fullscript, brand direct accounts).
Case study: NOW example and lab testing insights
NOW investigative case: a consumer bought a NOW product from Amazon; capsules looked different from the practitioner-sourced version.
NOW performed internal testing and found labels missing details and the product containing non-beneficial fillers (e.g., rice/potato derivatives) rather than the intended actives.
This illustrates that even well-known brands can be affected by counterfeit distribution and labeling gaps when sold through third-party marketplaces.
Analytical methods and the risk of relying on CoA without testing
High-Performance Liquid Chromatography (HPLC) as a key laboratory method to profile extracts.
Example: St. John’s Wort extract:
Desired constituents: hypericin (one of the key mood-modulating compounds) and hyperforin.
Some extracts labeled as St. John’s Wort were found via HPLC to have much lower or missing hypericin/hyperforin peaks; instead, peaks for other compounds (e.g., quercetin, linked to antihistamine effects) dominated.
Implication: a product with an apparently clean CoA may still be ineffective for its labeled purpose if the active constituents are missing or misrepresented.
If a company lacks in-house testing capability, it remains dependent on CoAs and cannot independently verify the presence and concentration of key constituents.
Classification of supplement companies by lab capability and oversight
Categories 1–2 (most questionable): private labeling and contract manufacturing with little to no control over raw materials or testing.
Private labeling: company purchases finished products from external manufacturers and applies its own label.
Contract manufacturing: the brand provides a formula to a manufacturer but has little control over raw materials, testing, or supply chain.
Example concern: a private-label brand may switch sources or formulations without consistent quality control; Mercola is cited as a cautionary example of a private-label approach.
Categories 3–4 (better but still limited):
Category 3: brands that manufacture their own products but do not operate their own laboratory.
Category 4: brands with certified manufacturing but their laboratory is not ISO certified.
Category 5: GMP-certified manufacturing and ISO-certified laboratory.
Only one company in this category: NOW brand.
Features: robust lab testing and production controls; ISO-certified lab reflects adherence to high international standards.
Category 6: brands that produce some of their own raw materials, have an ISO-certified lab, are directly FDA inspected, and maintain GMP-certified manufacturing.
Only one company in this category: Biotics Research.
Notable distinction: Biotics has pursued pharmaceutical licensing in certain jurisdictions; in the U.S., a pharmaceutical license is not required for supplements, but Biotics’ licensing leads to more rigorous testing and FDA oversight (including frequent inspections).
Practical implication: higher category numbers generally indicate stronger lab controls and reliability, though no system is perfect.
ISO, GMP, FDA, and the reality of third-party testing claims
ISO = International Organization for Standardization; certification signals adherence to high, internationally recognized lab procedures.
GMP = Good Manufacturing Practice; indicates controlled manufacturing environments and processes.
FDA oversight exists but is relatively minimal in many cases: the FDA does not require the breadth of testing that some third-party labels imply.
Third-party testing (e.g., NSF, USP) is often cited by brands, but compliance with FDA standards is the baseline, and some labs may test only selectively.
Anecdotal concerns:
A conference anecdote cited a statement that FDA rules permit a product to meet three of five sensory criteria (e.g., botanical appearance, smell, taste) to be considered acceptable—illustrating potential gaps in regulatory rigor.
Some manufacturers reportedly test only every few months rather than every batch, raising questions about batch-to-batch consistency.
Takeaway: third-party claims do not guarantee safety or efficacy; robust testing and ISO/GMP/FDA oversight are more meaningful indicators of quality.
Whole food supplements: benefits, limitations, and lab considerations
Question: are whole food-based supplements inherently better?
Key considerations:
Do these products have a laboratory to test for heavy metals, solvents, contaminants, and other residues?
Do they impose stricter contaminant limits than standard synthetic supplements?
Critical caveat: whole food supplements are often not provided in therapeutic doses; they frequently mimic food-level dosages rather than providing pharmacologically active levels.
Practical implication: for clients needing therapeutic outcomes, whole food supplements may be less cost-effective and less reliable for achieving dose-specific effects.
Practical guidance for practitioners and clients
Avoid purchasing supplements on Amazon or from unknown major retailers; seek trusted distribution channels (e.g., practitioner channels, Fullscript, direct brand accounts).
Encourage clients to evaluate brand quality using lab capabilities rather than relying solely on CoA or price.
Seek brands with clear GMP and ISO certifications, direct FDA oversight where possible, and transparent laboratory practices.
When possible, verify whether a company tests every batch versus only intermittently; inquire about specific tests conducted (heavy metals, solvents, contaminants, solubility, stability, expiry).
Consider whether the brand performs in-house testing or relies on external contract labs; assess the reliability of those labs (e.g., ISO certification, accreditation).
For private labeling or contract manufacturing brands, exercise caution about batch-to-batch consistency and raw material sourcing controls.
Takeaways on quality assurance and ethics
CoA alone is insufficient as sole evidence of product quality.
Regulators and independent assessments reveal that substandard or counterfeit products can appear legitimate on paper.
Consumers and practitioners should prioritize laboratories with ISO certification, GMP-compliant manufacturing, and direct FDA oversight when evaluating brands.
The ongoing counterfeit and mislabeling problem, including across high-profile retailers and marketplaces, necessitates vigilance in sourcing and ongoing testing beyond the CoA.
Quick reference: key numerical anchors from the transcript
NY AG (2015): 78 samples, 390 tests; 79 ext{%} DNA tests did not match labeled herbs.
Canada (2013): 44 products, 12 companies; only 2/12 met label claims; 10/12 did not.
Professional brands: hexavalent chromium found in 3/6 chromium supplements; lead found in 2/3 protein powders.
Amazon impersonation incident: NOW and others affected; investigations traced to facilities in Spain and Italy.
St. John’s Wort HPLC example: the expected peaks for hypericin and hyperforin were not present in a subpar extract; instead, peaks for other compounds (e.g., quercetin) dominated, indicating misrepresentation of active constituents.
ISO and lab leadership: Category 5 (NOW) has GMP manufacturing + ISO-certified lab; Category 6 (Biotics) has own raw materials, ISO lab, direct FDA inspections, and GMP manufacturing; Biotics cited as example with frequent FDA inspections (e.g., 278 inspections in a year).
FDA regulatory caveat: some products claim third-party testing, but FDA standards are minimal; a statement encountered suggested that “three out of five criteria” might be sufficient under some interpretations, underscoring potential loopholes in regulation.
Practical implications for exam-style understanding
CoA reliability is context-dependent; it should be supplemented with lab capabilities, batch testing, and supply-chain controls.
Understanding solvent use and testing is critical: FDA does not mandate solvent testing, so solvent residues can vary by manufacturer.
Real-world evidence (investigations by NY AG, Canadian studies, and counterfeit cases) demonstrates the risk of adulteration and label non-compliance in both retail and professional products.
Distinguishing among company categories (1–6) helps assess risk and inform sourcing decisions.
The distinction between whole food supplements and conventional supplements has practical implications for dosage, therapeutic outcomes, and cost.
Final synthesis
A robust approach to supplement quality requires more than a CoA: it requires trustworthy lab testing (preferably ISO-certified labs and GMP manufacturing with FDA oversight), transparent supply chains, scrutiny of raw material sourcing, and careful avoidance of high-risk distribution channels (e.g., unvetted marketplaces).
Clinicians should educate clients about these issues and guide them toward brands with demonstrated testing rigor and traceability, rather than relying on claims of third-party testing alone or on CoAs alone.