Ashwagandha: withanolides are the number that matters

Ashwagandha (Withania somnifera) is standardised to withanolides. That is the group of compounds used as the extract's marker — concentration is measured against it.

Which part of the plant

The label should say whether the root, the leaf or the whole plant is used. Different parts have different profiles, so “ashwagandha extract” without that detail is incomplete information.

The arithmetic

The withanolide amount comes from the extract weight and the percentage:

• SlimDay — 75 mg of extract, 10% → 7.5 mg of withanolides
• SlimNight — 100 mg, 10% → 10 mg
• ForceDay — 150 mg, 10% → 15 mg
• Ashwagandha (Essentials) — 300 mg of root, 5% → 15 mg

Look at the last two lines. 150 mg at 10% and 300 mg at 5% deliver the same. Twice the weight on the label does not mean twice the active.

On the word “adaptogen”

The term comes from herbalism and describes a category of plants; it is not an authorised health claim. The EU Register of nutrition and health claims holds no authorised claim for ashwagandha, so neither we nor anyone else may connect this ingredient to a specific effect on the body.

That is why our pages tell you what is in the capsule and how much of it — and do not tell you what it will do for you.

If you are comparing two products

Work out the milligrams of active per daily intake for both, rather than comparing extract weights. If one of them does not print a percentage, the calculation cannot be made and the comparison falls away.