SAC StudioThe ratio is backwards for the studied effect
Double Wood offers 120 vegan caps of 500 mg extract at a strong price, third-party tested and made in the USA. The catch is on the label: it's a two-part blend — 375 mg standardized to 3% salidrosides only, plus 125 mg standardized to 1% rosavins / 3% salidrosides — which works out to about 15 mg salidrosides but only ~1.25 mg guaranteed rosavins per capsule (roughly 0.25% of the 500 mg total), the inverse emphasis of the 3% rosavins / 1% salidroside SHR-5 extract most human fatigue trials used. If you want the studied profile, this isn't it, and the label is easy to misread.
The label is a two-row blend: 375 mg standardized to 3% salidrosides only, plus 125 mg standardized to 1% rosavins / 3% salidrosides. That works out to roughly 15 mg salidrosides but only about 1.25 mg guaranteed rosavins per capsule — a ~12:1 salidroside-to-rosavin ratio, far more skewed than the SHR-5 profile the fatigue trials used. Because rosavins are guaranteed in only a quarter of the total extract, we've lowered this score from our earlier read (4.5 to 4.0) now that the two-row math is spelled out.
500 mg total extract (375 mg + 125 mg) overshoots the 200-400 mg window used in the trials, and the guaranteed rosavin content is only about 1.25 mg per capsule — roughly four times lower than a flat '1% of 500 mg' read would suggest. That gap between total extract weight and actual guaranteed actives is why we've nudged this score down slightly (6 to 5.5).
Third-party tested, gluten-free, made in the USA. Reasonable transparency for a value brand, though not at the practitioner-brand level.
A standard vegan capsule of root extract, gluten-free. Generally well tolerated, though the higher relative salidroside may feel more stimulating for some — start low and take early in the day.
120 vegan caps at ~$18 is a genuinely good per-cap price and a long supply — value is the main thing going for it.
“Double Wood delivers the studied rhodiola profile”
Only 125 mg of the 500 mg is standardized to 1% rosavins; the remaining 375 mg is standardized to salidrosides alone — the opposite emphasis to the rosavin-forward SHR-5 extract (3% rosavins / 1% salidroside) used in the classic fatigue trials (Darbinyan 2000, PMID 11081987; Spasov 2000, PMID 10839209).
“It's third-party tested and made in the USA”
Double Wood states third-party testing, gluten-free formulation and US manufacturing — reasonable QC basics for a value brand.
An earlier version of this review said Double Wood's rhodiola was standardized to '3% salidrosides / 1% rosavins' as a single 500 mg extract. The Supplement Facts panel reads: 375 mg Rhodiola Rosea Root Extract at 3% salidrosides, plus a separate 125 mg Rhodiola Rosea Root Extract at 1% rosavins / 3% salidrosides — guaranteed rosavins work out to about 1.25 mg per capsule, not the ~5 mg a single-extract reading implies. We re-read the label on Sep 3, 2026 and revised the lead, TL;DR, specs, claim evidence, findings and verdict text, and lowered Standardization & Extract Match 4.5 → 4.0 and Dose vs Clinical Range 6 → 5.5 (overall 5.8 → 5.5).
The label reads '3% Salidrosides' on the 375 mg row and '1% Rosavins / 3% Salidrosides' on the 125 mg row — easy to skim as one 3%/1% extract. In fact the '1% Rosavins' line covers only a quarter of the capsule (125 mg of the 500 mg total), so the guaranteed rosavin content is roughly 1.25 mg, not the ~5 mg a quick read implies.
At ~$0.15/cap this is cheap, and the testing is fine. But on a list where standardization to the studied profile is the axis, an inverted ratio caps how high it can rank regardless of price.
Double Wood is a fine value product with real testing, but its salidroside-forward blend — about 15 mg salidrosides to only ~1.25 mg guaranteed rosavins per capsule — is the wrong chemistry for the stress-fatigue evidence. Choose a rosavins-forward 3%/1% cap like Life Extension or NOW if you want what the trials actually used.
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Correct min 3% rosavins / 1% salidroside at similar value from a more auditable brand — the same price tier done right.
See it on the list →The rosavins-forward profile at the trial dose, cheaply — the studied-effect pick over an inverted ratio.
See it on the list →Benefit was tied to the rosavins-forward SHR-5 extract, not an inverted salidroside-dominant ratio.
The fatigue benefit came from a 3% rosavins / 1% salidroside extract — the opposite of Double Wood's ratio.
