How we measure supplements

Every supplement page on this site records the same six measurements, in the same order, using the same rules. That consistency is the point. If ashwagandha and rhodiola are described by different criteria, you cannot really compare them, and neither can anyone quoting us.

The six measurements

Dose used in trials

The daily amount, and the duration, used in the published human trials we cite. Where the trials disagree we give the range rather than picking a flattering number from one of them. If the human evidence is one small study, that is what this line says.

Dose in our pick

What the product we recommend actually delivers per serving, read off the current label. A product can sit well below the trialled dose and still be the best available option, and when that happens we say so on the page rather than quietly leaving the gap out.

Standardised form

Whether the label names a branded or standardised extract with its own trial record, such as Suntheanine or KSM-66, or whether it simply names the plant. This matters more than most buying guides admit. A trial run on one standardised extract does not automatically transfer to a generic powder from the same plant, because the compound ratios differ.

When a label does not state the form, we record "not stated" instead of assuming. Plenty of unnamed material is perfectly good. We just cannot verify it, and we would rather you know which of the two situations you are in.

Third-party tested

Whether an independent programme has tested the specific product, and which one. NSF, USP and IFOS are the ones that appear most often in this category. Manufacturer in-house testing does not count here, because the point of the line is independence.

Other actives

Anything else in the capsule with a pharmacological effect. A theanine product carrying an undisclosed 100 mg of caffeine is a different product from a plain one, and stacked formulas make it harder to tell what is working when something does work.

Reported onset

Roughly how long before effects show up in the trials, since this is the question people ask after they have already bought something. Some ingredients act within an hour. Others need six to eight weeks of daily use before anything is measurable, and knowing that in advance prevents a lot of wasted money.

Where the values come from

Dose, form, third-party testing and other actives are read from the live product listing on the day we check it, and the date is printed on the page. Trial doses and onset windows come from the papers we link. Nothing on these pages is generated from a manufacturer's marketing copy.

What we do not do

We do not run laboratory assays. We cannot tell you whether the contents of a capsule match its label, and any site claiming otherwise without an accredited lab behind it is overstating what it knows. What we verify is what the label claims, what the evidence supports, and whether those two things line up.

We also do not quote prices we cannot keep current. Retailers change prices constantly, and a stale figure is worse than none.

Money

Links to retailers are affiliate links, so a purchase can earn us a commission. Nobody pays to appear on a page or to be chosen as a pick, and the criterion for each product is published before the recommendation so you can check our reasoning against it. Where the cheaper option is genuinely fine, the page says that too.

Read the full affiliate disclosure or the editorial standards behind these pages.