Hyponatremia (lower-than-normal blood sodium) is usually associated with:

1. Hyponatremia describes an abnormally low sodium concentration in blood. 2. This can happen either from an absolute loss of sodium or from a relative dilution. 3. The text specifically says hyponatremia is usually associated with excess water accumulation diluting the sodium. 4. Excess dietary salt would raise, not lower, sodium concentration, so that option is ruled out. 5. So excess water accumulation diluting sodium is correct. _Source: OpenStax Anatomy and Physiology (CC BY 4.0), Ch 26 "Fluid, Electrolyte, and Acid-Base Balance", p.1260 §Sodium_