During-effort fuel · electrolyte · reviewed 26 Aug 2026

Nuun Sport 37

Item: Nuun Sport
Rating: 37
Author: Lourenço Faria e Maia

Nuun / 1 tablet in 16 fl oz water / 300 mg sodium / $0.75

The most widely available tablet here, with all four electrolytes present, but at $2.50 per 1000mg of sodium it costs more than twice what 4Endurance Electrolytes ($1.08) charges for the same dose.

Score breakdown

Each dimension below is scored 0 to 100 against a fixed scale, not against the rest of the catalog, so adding a product never moves this number. The overall score is the average of the dimensions this product declares data for. How the scales are set →

37/100

Mixed

Sodium dose ?Sodium per serving, on a scale topping out at 1000 mg, a single dose covering the top of what's typically lost to sweat in an hour.30

Value (cost/1000mg Na) ?What it costs to get 1000 mg of sodium from this product. Not physiological: a market-based scale from $3.00 (0) to $1.00 (100).25

Potassium ?Potassium per serving, on a scale topping out at 200 mg, roughly the upper end of typical hourly sweat loss.75

Calcium ?Calcium per serving. Weaker grounding than sodium/potassium: sweat calcium loss is minor and not really a primary target during exercise; the 100 mg ceiling is this catalog's practical high end, not a physiological one.13

Magnesium ?Magnesium per serving, on a scale topping out at 60 mg, roughly matching cited hourly sweat-loss ranges.42

Cost per 1000mg sodium

$2.50/1000mg

Sodium per tablet

300mg

Comparison

5 of 14 electrolytes held

Prices per single sachet at the cheapest box size we track. Best in green, worst in red, across the gels shown.

Measure	Nuun Nuun Sport	LMNT LMNT Citrus Salt	Precision Fuel & Hydration Precision Fuel & Hydration PH 1000	Science in Sport SiS GO Hydro	4Endurance 4Endurance Electrolytes
Overall scoreAn average of the various variables measured.	37	75	36	44	50
SodiumThe main electrolyte lost in sweat, and the biggest single driver of cramping and hyponatremia risk.	300 mg	1000 mg	500 mg	345 mg	250 mg
PotassiumWorks alongside sodium in muscle and nerve function.	150 mg	200 mg	130 mg	65 mg	70 mg
CalciumInvolved in muscle contraction; lost in far smaller amounts than sodium.	13 mg	0 mg	20 mg	102 mg	10 mg
MagnesiumSupports muscle and nerve function; some evidence it blunts cramping.	25 mg	60 mg	10 mg	8.1 mg	50 mg
CarbohydrateMinimal by design. This is a hydration product, not a fuel source.	4 g	0 g	3 g	0.9 g	0 g
Price per tabletWhat one tablet costs.	$0.75	$1.50	$1.20	$0.75	$0.27
Cost per 1000mg sodiumThe only price that compares across different sodium concentrations.	$2.50	$1.50	$2.40	$2.17	$1.08

Verdict

what it does · what it costs

What it does well

All four electrolytes declared: sodium, potassium, calcium, and magnesium.
Widely stocked at retail, easy to find in stores rather than online-only.
4 g of carbohydrate provides a small amount of fuel alongside hydration.

What it costs you

300 mg of sodium is a middling dose for an effervescent tablet; Precision's PH 1000 and PH 1500 carry 500 mg and 750 mg.
$2.50 per 1000mg of sodium, mid-pack in this set: LMNT ($1.50) and 4Endurance Electrolytes ($1.08) get there for less.
15 kcal and 4 g carbohydrate mean it isn't a zero-calorie option if that matters to you.

Where to buy

Prices and links as last checked. The price next to the name above is per unit at the cheapest box size we track; a single-unit price below may run higher.

Nuun $7.49 tube of 10 Visit →

Who this is for

the numbers, applied

The field tells you what it is. This is who should act on it.

Worth the money if

You want the most widely available option on a store shelf.
You want a complete four-electrolyte profile without hunting for it.

Look elsewhere if

You want the lowest cost per 1000mg of sodium.
You want a zero-carbohydrate, zero-calorie product.