Coconut Water

Food · Drink · Food, Typed Supps

Sold as nature’s sports drink. It has the wrong electrolyte for the job.

Stage by stage

Low sugar (Mouth): Around 4.7 g of sugar per 100 g — well under half what a soft drink carries.
Absorption (Stomach): Low osmolality empties quickly, so fluid arrives fast.
Potassium (Circulation): 200 mg per 100 g — genuinely high, and not the electrolyte sweat depletes.
Sodium gap (Extracellular fluid): At 17 mg per 100 g, too little sodium to drive fluid retention after heavy sweating.

Timing

The one context where it genuinely underperforms is after prolonged heavy sweating, where the missing sodium matters. For everyday drinking there is no timing question.

Time to effect

20–30 min: Fluid absorbed.
—: No cumulative benefit; this is a drink, not an intervention.

Allergens

None of the fourteen major allergens. Derived from what this food is, not from a product label.

Eating patterns

Fits: Vegan, Vegetarian, Pescatarian, Halal, Kosher, Keto, Gluten-free. Depends on the product: Low-FODMAP.

Satiety

Not scored: the satiety index is measured on 240 kcal servings, and nobody eats a 240 kcal serving of this. The question does not apply rather than the answer being unknown.

Cost band

Cheap — roughly £2 per kg, as a band midpoint rather than a price.

Key nutrients

Nutrition per 100g

Calories: 21
Protein: 0.5g
Carbohydrate: 4.7g
of which sugars: 4.7g
Fat: 0.1g
of which saturated: 0.1g
Sodium: 17mg

Food vs. supplement

Oral rehydration solutions are built around sodium and glucose because that combination drives water across the gut wall. Coconut water has neither in the right proportion, which is why it performs like water rather than like a rehydration salt.

Kitchen tip

If you are drinking it after a long, hot session, add a pinch of salt or eat something salty with it. Otherwise you are topping up the electrolyte you kept and skipping the one you lost.

Common myth

“Coconut water is nature’s sports drink.” In reality: It is high in potassium and low in sodium, and sweat is the opposite — you lose roughly ten times more sodium than potassium. That makes it a pleasant, low-sugar drink and a poor rehydration fluid for anything long or hot, where the sodium is what drives the water back into your body. A pinch of salt fixes it entirely.

Recipes that use it

Tropical Mango Smoothie