Ranked by evidence
Best supplements for hydration and electrolytes
For hydration, the one thing with strong evidence is sodium: a drink that contains it is retained better than plain water after heavy sweat losses. Everything below is ranked by the evidence for rehydration specifically, not by popularity, and most of it only matters if you sweat hard for more than an hour. On a normal day, a typical diet already supplies the sodium and potassium you need for fluid balance.
Picks are ranked by the strength of published evidence for this goal in otherwise healthy adults. A persistent symptom needs a clinician's evaluation, and no supplement on this list replaces treatment.
Evidence last reviewed: September 2026
Top picks
| Option | Evidence | Best for | The honest note | |
|---|---|---|---|---|
| Electrolyte Powder | Moderate evidence | rehydrating after heavy sweat loss | Sodium in the drink reduces urine output and helps restore plasma volume, so it is retained better than plain water over 2–4 hours. It does not prevent hyponatremia from drinking too much, and everyday use without heavy sweating has no trial support. | View |
Solid options
| Option | Evidence | Best for | The honest note | |
|---|---|---|---|---|
| Endurance Formulas | Moderate evidence | long, hot endurance sessions | A systematic review found carbohydrate-electrolyte drinks effective for restoring fluid balance, and the carbohydrate itself has strong evidence for endurance performance. Drinking far beyond thirst still risks hyponatraemia. | View |
| Coconut Water Powder | Limited evidence | a palatable post-exercise drink | In crossover trials it rehydrated about as well as a sports drink or water, not better. It is low in sodium, so for long or hot sessions add salt or an electrolyte product. | View |
Situational
| Option | Evidence | Best for | The honest note | |
|---|---|---|---|---|
| Glycerol | Moderate evidence | pre-loading before long events in heat | Glycerol with sodium reliably retains extra fluid before exercise, but the extra 1–1.5 kg of water has to be carried and performance gains are inconsistent. Only worth trying for long, hot events, and practise it in training first. | View |
Popular for this goal — but the evidence says skip
- Pink Himalayan Salt Limited evidence
It is 96–99% sodium chloride, so any hydration benefit comes from the sodium every salt provides, and it lacks the iodine of iodized table salt.
- Salt Tablets Limited evidence
One hot half-ironman trial found a benefit, a trial in cool conditions found none, and they do not reliably prevent hyponatremia, which is driven mainly by drinking too much.
- Hangover Formulas Limited evidence
Trials have not shown that their electrolytes and B vitamins reduce hangover severity beyond drinking water.
- Leg Cramp Formulas Limited evidence
The Cochrane review concluded magnesium is unlikely to meaningfully reduce idiopathic cramps in older adults, and the added potassium or calcium has no cramp-specific trial support.
Our verdict
If you sweat heavily for more than an hour, a sodium-containing electrolyte drink is the pick, and a carbohydrate-electrolyte mix does the same job in long endurance sessions. Skip pink salt, salt tablets taken as hyponatremia insurance, and hangover or cramp formulas sold on electrolyte claims.