Supplement
Electrolytes
Sodium, potassium, magnesium around training in heat. Not a general-use supplement.
What it does
Contextual, not routine. Useful around high-volume sweating — long or hot training, prolonged endurance work — not at typical activity levels. The "low sodium is dangerous" longevity narrative has overshot the evidence.
Sodium maintains extracellular fluid volume and supports nerve and muscle function; substantial unreplaced sweat loss compromises both.
What the evidence shows
Overall evidence strength: Moderate certainty
Who it's for, who should skip
Around training in heat or prolonged endurance work. Most adults at moderate activity are fine with normal dietary intake.
Running it
- Form
- oral
- Dose
- as needed around activity in heat or prolonged endurance
Access & cost
Available over the counter.
Last reviewed 27 August 2026.