Nuun · Electrolytes · Tablets
Is Nuun Sport underdosed?
1 serving = 1 tabletDirections: 1–3 servings a dayLabel as of 22 Jun 2023 · NIH DSLD
Verdict
632 mg per litreas the directions mix it · the AIS guide is 500–700 mg per litre
Reaches the guideOne serving has 300 mg of sodium. Mixed with 475 mL of water as the label directs, that is 632 mg per litre; the AIS's general guide is 500–700 mg per litre. Sweat sodium differs a lot between people, so the guide is a starting point.
It ranks 7th of 11 electrolyte supplements here by dose.
What the label says
- Sodium per serving
- 300 mg in 1 tablet
- Water, as directed
- 475 mL
- Sodium per litre
- 632 mg per litre
- The AIS guide
- 500–700 mg per litre Evidence: Moderate
Directions for use Add 1 tablet to 16 fl oz/475 ml of water up to 3 times a day.
Also on the label
| Ingredient | Per serving | Verdict |
|---|---|---|
| Calcium (Calcium Carbonate) | 13 mg | Not graded |
| Magnesium | 25 mg | Not graded |
| Chloride (Potassium Chloride) | 40 mg | Not graded |
| Sodium | 300 mg | Not graded |
| Potassium (Potassium Bicarbonate, Potassium Chloride) | 150 mg | Not graded |
More about sodium per litre, as mixed: forms, timing and the studies behind the dose.
Same category, compared
All 11 electrolyte supplements we checked, ranked by dose (commission never changes the order). Sodium per litre as each label mixes it.
| Product | Per litre | Form |
|---|---|---|
| Cure Hydrating Electrolyte Mix | 507–1,014 mg per litre | Powders |
| DripDrop Electrolyte Powder | 1,395 mg per litre | Powders |
| DripDrop Zero Sugar Electrolyte Powder | 1,395 mg per litre | Powders |
| Liquid I.V. Hydration Multiplier | 1,057 mg per litre | Powders |
| Redmond Re-Lyte Hydration Electrolyte Powder | 856–1,712 mg per litre | Powders |
| Skratch Labs Hydration Sport Drink Mix | 800–1,143 mg per litre | Powders |
| Nuun Sport (this product) | 632 mg per litre | Tablets |
| Ghost Hydration | 362–423 mg per litre | Powders |
| Nectar Essential Daily Hydration Packets | 211–423 mg per litre | Powders |
| Kaged Hydra-Charge | 222–355 mg per litre | Powders |
| Just Ingredients Electrolytes | 278–324 mg per litre | Powders |
Where the reference doses come from
- Sodium per litre, as mixed, 500–700 mg: AIS, 2025.
- Label data: National Institutes of Health, Office of Dietary Supplements. Dietary Supplement Label Database, 2026. https://dsld.od.nih.gov/. Label 291597, including its servings a day.
For a supplement taken as one dose we judge one serving, and show the most the label allows in a day. Read the full methodology or the corrections log.