Glossary
The vocabulary of the supplement aisle, translated — each term linked to the article where it matters.
Adaptogen
A plant compound claimed to help the body "adapt" to stress. The label covers very different plants with very different evidence — rhodiola and ashwagandha are the best-studied. Read more →
Bioavailability
How much of an ingested substance actually reaches your bloodstream. The reason magnesium oxide (≈4%) and magnesium glycinate (far better) are different products despite the same mineral. Read more →
Bisglycinate
Magnesium bound to two glycine molecules — the chelated, bedtime-friendly form usually sold as "glycinate." Read more →
Certificate of Analysis (COA)
A lab report for a specific production batch verifying contents and purity. The single document that separates honest supplement brands from label-printers. Read more →
Cortisol
The body's primary stress hormone, following a daily rhythm. Chronically elevated evening cortisol is a common driver of stress-related sleep trouble; ashwagandha trials measured ~20–30% reductions. Read more →
Elemental magnesium
The amount of actual magnesium in a compound, as opposed to the compound's total weight. Dosing guides (200–400 mg) refer to elemental — always check the back panel. Read more →
GABA
The brain's main inhibitory ("quiet down") neurotransmitter. Magnesium supports its function; oral GABA supplements mostly cannot cross into the brain — which is why we don't rank them. Read more →
Half-life
The time for a substance's level to halve. Caffeine's ~5–6 hour half-life is why a 4 p.m. coffee is still one-quarter active at midnight. Read more →
KSM-66
A patented root-only ashwagandha extract standardized to 5% withanolides — the extract behind most positive stress and sleep trials. Read more →
Melatonin
The pineal hormone signaling biological night. A clock-shifter (great for jet lag and shift work), not a sedative — and effective at 0.5–1 mg, far below typical bottle doses. Read more →
Sensoril
A root-and-leaf ashwagandha extract standardized to ~10% withanolides; fewer trials than KSM-66 but a solid record at 125–250 mg/day. Read more →
Standardized extract
An herbal extract guaranteed to contain a defined percentage of marker compounds. Non-standardized "root powder" products are agricultural material, not supplements. Read more →
Structure/function claim
The legal supplement claim format ("supports restful sleep") — distinct from disease claims ("treats insomnia"), which are illegal for supplements. We hold this line without exception. Read more →
Third-party testing
Independent lab verification of a product's contents (NSF, USP, Informed Choice). The shortcut replacement for reading COAs yourself. Read more →
Withanolides
The active steroidal lactones in ashwagandha; the percentage that defines extract potency (5% root-only for KSM-66, ~10% for Sensoril). Read more →