Why ORS Was Never Meant for Your Workout
ORS (Oral Rehydration Salts) was developed by the World Health Organization in the 1970s as a breakthrough treatment for one of the deadliest health issues in the world at the time: dehydration caused by severe diarrhea. In many developing countries, especially among infants and young children, diarrheal diseases were leading causes of death. ORS—a carefully balanced mix of sodium, glucose, potassium, and citrate—enabled caregivers to rehydrate children quickly and effectively, even without access to hospitals. It’s been called one of the most important medical advances of the 20th century.
But it’s not for everything.
While ORS is effective for rehydrating individuals suffering from diarrhea-induced dehydration, it’s not designed for people losing fluids primarily through sweat.
When we sweat—whether from movement or heat—we lose water and electrolytes, particularly sodium. This kind of dehydration affects thermoregulation, cardiovascular function, and performance in ways that are very different from illness-related dehydration.
Here's how sweat loss dehydration differs:
Different Electrolyte Ratios
ORS typically contains around 500-700mg of sodium per liter. However, sweat contains approximately 800-1500mg of sodium per liter, depending on the individual's sweat rate and acclimatization. This means ORS simply doesn't provide enough sodium to replace what's lost during intense exercise.
Performance Implications
When sodium levels drop too low during exercise (hyponatremia), performance suffers dramatically. Symptoms range from muscle cramps and weakness to more serious conditions like confusion and seizures in extreme cases. Athletes need formulations specifically designed to maintain optimal electrolyte balance during activity.
Glucose Isn't Always Necessary
ORS includes glucose because it enhances sodium and water absorption in the gut—crucial when someone is experiencing diarrhea. But during physical exertion or heat-related sweating, we’re not usually dealing with damaged intestinal absorption. For many people, especially those avoiding excess sugar, glucose in rehydration formulas is unnecessary and even counterproductive, potentially causing energy crashes or gastrointestinal discomfort.
Modern Needs Demand Modern Formulations
ORS was a life-saving solution for a very specific, life-threatening problem. But hydration isn’t one-size-fits-all. In today’s world, most dehydration comes not from illness, but from activity, heat, or simply not drinking enough throughout the day. That calls for a different kind of electrolyte solution—one that matches what we actually lose through sweat, not what’s lost during digestive illness.