Supplement Label Index

Potassium Citrate vs. Potassium Aspartate

Among 3,345 on-market potassium products with an identifiable primary form, 36.8% use Potassium Citrate (1,232 products) and 9.3% use Potassium Aspartate (310).

Potassium CitratePotassium Aspartate
Quality tierTier 1Tier 2
Potassium by weight36.2%22.8%
Share of market36.8%9.3%
On-market products1,232310
Median declared dose50 elemental mg
middle half: 30–99
50 elemental mg
middle half: 25–99
Most common brandsSource Naturals, Wonder Laboratories, Life ExtensionDouglas Laboratories, Bluebonnet, Pure Encapsulations

Doses are declared per serving in elemental mg. “By weight” is the share of the ingredient that is the nutrient itself (e.g. elemental magnesium in a magnesium salt).

Why Potassium Citrate is tier 1

Treated as equivalent to potassium chloride (tier 1) on the basis of reported bioequivalence in absorption, but no primary absorption/PK comparison was verified; preferred clinically for kidney-stone prevention/urinary alkalinization rather than for an absorption advantage.

Source: none verified for the absorption claim (Sakhaee K et al. 1991, J Clin Endocrinol Metab 72(2):396-400, PMID 1899422 compares potassium salts on renal citrate excretion, not absorption)

Why Potassium Aspartate is tier 2

No dedicated comparative bioavailability study located; assumed acceptable given the label cross-check.

Source: none located (no comparative bioavailability study found)

Tiers summarize published comparative bioavailability or outcome evidence for each form (see methodology). This page describes the market; it is not a recommendation to take either form. Talk to a clinician about what's right for you.

Other potassium comparisons