Electrolyte Drinks Ranked by What's Inside

We analyzed the nutrition panels of 15 popular electrolyte drinks and ranked them by what actually matters for exercise performance: sodium content per serving, potassium-to-sodium ratio, magnesium presence, and sugar per calorie. Dr. Stacy Sims — exercise physiologist at Stanford University and author of the landmark research on sex-specific hydration — reviewed our methodology. The results expose how many brands prioritize taste over function.

Sodium is the primary electrolyte lost in sweat. Dr. Lawrence Armstrong's Human Performance Laboratory at the University of Connecticut has measured sweat sodium losses across hundreds of athletes: the range is 300-1,200 mg per liter, varying by genetics, heat acclimatization, and fitness level. Most commercial sports drinks contain only 100-200 mg of sodium per serving, which is inadequate for athletes sweating heavily. You would need to drink three bottles of a typical sports drink to replace what you lose in one hour of hard training.

Our top-ranked drinks contain 500-1,000 mg of sodium per serving, adequate potassium (200-400 mg), and magnesium (50-100 mg). They use minimal sugar — enough to enhance sodium absorption through the SGLT-1 transporter in the gut (about 10-15 grams) but not the 34 grams found in standard sports drinks.

The worst offenders are the mass-market sports drinks that contain more sugar than a can of soda with negligible electrolyte content. They are marketed to athletes but formulated for taste. If you are drinking one of these, you are consuming liquid candy with a sports label.

A cheaper alternative: make your own. One liter of water, half a teaspoon of salt (1,150 mg sodium), a quarter teaspoon of salt substitute (500 mg potassium), and 2 tablespoons of honey or maple syrup (15 grams of carbs). Total cost: about $0.15 per liter. It outperforms most commercial options and matches the osmolality range (200-300 mOsm/L) that Dr. Jeukendrup's research identifies as optimal for gastric emptying during exercise.