planb7 asks:

Can a person taking Indigo-3G® also take apple cider vinegar and cinnamon extract? Would they work well with Indigo or work against it?

Shouldn’t be any problems at all. ACV and cinnamon shouldn’t affect Indigo-3G because they work differently in the body.

Something like ACV before meals or at bedtime, cinnamon with meals, and Indigo-3G as per label directions (before dinner and/or before training) should be a pretty solid “stack” (though it’s weird using that term to describe eating foods) to improve insulin sensitivity.