The chief active nutrients of Ashwagandha are called withanolides. Many of the scientific studies have focused on these key components. The quality of a Ashwagandha supplement is dependent on the manufacturer testing of withanolides levels and insuring that the raw ingredients contain a minimum amount. When choosing an Ashwagandha supplement, you will want to make sure that the ingredients are “standardized” to contain a minimum of amount of these nutrients. Vitabase Ashwagandha is standardized to provide a minimum of 4.5% of these nutrients.