I’ve done multiple prolonged water fasts: 4-day, 5-day, 7-day and 40-day. Never took vitamins as instead relied on nutrients release by ketosis. Drank water only. But my primary goal was NOT weight loss, it was the canibilization of dead and senescent cells from my major organs and the cranking up of production of stem cells in the liver. Coffee and herbal teas have xenobiotics, substances not naturally produced by the body and have to be metabolized in the liver. However, during my recent ReFeed and starting a new Restore and Rebuild Lean Muscle phase my goal has changed and I’m drinking coffee and considering it NOT breaking fast as my goal has changed.
Bottom-line: If your goal is weight loss, the herbal tea won’t break fast and its more of a personal choice regarding the vitamins in my humble opinion.
Hope this helps! Good luck!