A granulated nutritional supplement dispensing machine extracts single-serving doses from a multi-serving supplements cartridge for delivery as a drinkable solution. A lead serving chamber is pierced so that its powered contents drain into a mixing cup together with a metered quantity of water from an integrated water tank. A vibrator unit assists drainage of the granulated materials from the lead serving chamber. The mixing cup is rotated at high speed to blend the water and supplements into a slurry. The supplements cartridge is indexed after (or before) use so that an unopened serving chamber is presented each time for extracting its supplements. This enables partially-used supplements cartridges to be used in the machine, as is conducive in multiple-user households. The supplements cartridge is configured with read-write data capability to indicate whether or not the contents of each serving chamber have been emptied.