When buying standardized extracts...

The amount of an active or main ingredient in a standardized herbal extract is often expressed as a percentage: milk thistle 'standardized to contain 80% silymarin' means that 80% of the extract contains that ingredient. Accordingly, recommendations in this blog for most standardized products are given as percentages. For example, a 150 mg dose of milk thistle standardized to contain 80% silymarin contains 120mg silymarin (150 x .80 = 120). Sometimes, though, a standardized extract product will simply state the actual amount of active ingredient you're getting (for example, 120 mg silymarin), rather than listing a percentage.