Potassium is the main intracellular cation, necessary to maintain the normal resting potential of the cell membrane [1]. It is predominantly found inside cells, while its partner — sodium — predominates outside. Their joint cooperation (the so-called sodium-potassium pump) generates electrical impulses in the body. Thanks to this, potassium determines proper contractions of all muscles (including the heart muscle), nerve conduction and maintaining water and acid-base balance. [2]. In the case of potassium deficiency (hypokalemia), the resting membrane potential is more negative, which causes muscle weakness, cardiac dysfunction seen in EKG and arrhythmia [1].
What it contains: Muscle meat (beef, pork, poultry, fish; salmon, trout, cod) and offal. As an addition: sweet potatoes (always cooked), pumpkin, zucchini, carrots, spinach, bananas (as a delicacy). With a balanced home diet, additional potassium supplementation is not required [2].
Deficiency: In the BARF diet, where meat and offal are naturally very rich in potassium, nutritional deficiencies are virtually non-existent in healthy dogs and cats. A distinction is made between total potassium deficiency in the body and extracellular (or plasma) [1]. Total results from excessive loss of potassium from the gastrointestinal tract and kidneys (chronic diarrhea, vomiting, diuretics, and especially chronic renal failure in cats) [3] [4]. Often there are no clinical symptoms, sometimes muscle weakness, polyuria and polydipsia appear. Supplementation guidelines are guidelines only. Due to the inconsistency between intracellular potassium and plasma potassium levels, [1] should be regularly monitored.
Excess: In healthy animals, excess potassium from a meat diet is excreted in the urine on an ongoing basis, so food poisoning with this element does not occur. [4].
Sources
- DiFazio, J. (2018). Potassium supplementation. In K. J. Drobatz, K. Hopper, E. Rozanski, & D. C. Silverstein (Eds.), Textbook of Small Animal Emergency Medicine (chap. 173, pp. 1136–1139). Wiley-Blackwell. https://doi.org/10.1002/9781119028994.ch173
- National Research Council (2006). Nutrient Requirements of Dogs and Cats. National Academies Press. https://nap.nationalacademies.org/catalog/10668/nutrient-requirements-of-dogs-and-cats
- Dow SW, LeCouteur RA, Fettman MJ, Spurgeon TL (1987). Potassium depletion in cats: hypokalemic polymyopathy. JAVMA 191(12). https://pubmed.ncbi.nlm.nih.gov/3693009/
- MSD (Merck) Veterinary Manual. Overview of Disorders of Potassium Metabolism in Animals. https://www.msdvetmanual.com/metabolic-disorders/disorders-of-potassium-metabolism/overview-of-disorders-of-potassium-metabolism-in-animals