Dietary anions control potassium excretion: it is more than a poorly absorbable anion effect

Dietary anions profoundly impact K⁺ homeostasis. Here, we found that a K⁺-rich diet, containing [Formula: see text] as the counteranion, enhances the electrogenic K⁺ excretory machinery, epithelial Na⁺ channels, and renal outer medullary K⁺ channels, much more than a high-KCl diet. It also uniquely induces KCC3a and pendrin, in B-intercalated cells, providing an electroneutral KHCO₃ secretion pathway. These findings reveal new K⁺ balance mechanisms that drive adaption to alkaline and K⁺-rich foods, which should guide new treatment strategies for K⁺ disorders.