Do I need to take it on an empty stomach?

You do not need to, however, some of the best results in ingredients with clinical trials were on an empty stomach.  If you have a sensitive gut or prefer to mix it a smoothie, you should still see benefits. Also you can check out dosing guidelines here: 

• Dosing:
  • Week 1: ½ scoop daily
  • Week 2+: Full scoop daily
• For sensitive guts, consider dosing as follows:
  • Week 1: ¼ scoop, as tolerated and/or taken with food
  • Week 2: ½ scoop, as tolerated and/or taken with food
  • Week 3+: full scoop, as tolerated and/or taken with food