Evidence Library
Can DNA Barcoding Verify a Herbal Supplement?
DNA methods identify plant species, but processing destroys DNA and an identity match cannot measure dose or purity. The famous 2013 study was retracted.
Evidence Library
Supplement evidence: regulation and safety
Numbered reviews of the regulatory and safety evidence behind supplements. Each one takes a single question, states the bottom line up front, and marks plainly where the record runs out.
Most supplement writing argues from a conclusion backwards. These reviews go the other way: one question, the strongest available evidence, and an explicit account of what that evidence cannot settle. Each is dated, numbered, and downloadable as a PDF carrying the same sources as the page.
The regulatory pair explains the framework: how supplements are regulated differently from medicines, and what it took for a regulator to remove an entire ingredient class. The testing pair covers verification: what a “third-party tested” seal actually proves, and whether DNA barcoding can authenticate a herbal product.
Two reviews examine specific harms: the 2013 OxyELITE Pro liver-injury outbreak, and how much vitamin D is too much. Much of the primary evidence is American, because that is where the investigations and the enforcement record sit; each review notes how the position differs in New Zealand.
Evidence LibraryWhy the FDA Banned Ephedra Supplements
The 2004 rule shows post-market evidence removing an entire class of supplement ingredients — and how long that took to assemble and enforce.
Evidence LibraryHow Much Vitamin D Is Too Much?
The adult upper intake level is 4,000 IU a day, but that limit is not a toxicity switch. Risk depends on dose, duration, blood calcium and medical context.
Evidence LibraryOxyELITE Pro and the 2013 Liver-Injury Outbreak
A cluster of severe hepatitis was linked to one supplement. The epidemiology supported the association; the exact toxic ingredient was never confirmed.
Evidence LibraryHow Supplements Are Regulated vs Medicines
Supplements are not unregulated. The difference is that most reach the market without approval, while a new medicine must prove safety and effect first.
Evidence LibraryWhat a "Third-Party Tested" Seal Proves
Certification seals verify identity and screen for banned substances. They do not verify that a supplement works, or that an untested batch is clean.