The phrase is often metaphorical and does not involve physical 'standing' or 'turning'. The latest findings stand our knowledge of nutrition on its head.
Pro Tip 2/3
Unexpected Change
It implies a surprising or unforeseen reversal of what was previously accepted. His win turned the predicted results on their head.
Pro Tip 3/3
Impactful Reversal
This phrase signifies a change that has profound effects or significance. The new evidence turned the whole argument on its head.