Commercial influences may have corrupted the American College of Sports Medicine’s hydration guidelines.
If you had to name the greatest medical advance over the past two centuries, what would you pick? Smallpox vaccine jumped to my mind, then I remembered it was discovered back in the 1700s. The British Medical Journal compiled a list of 15 contenders, but which would take the crown? Would it be anesthesia, which makes it possible to be asleep during surgery? Would it be antibiotics? Another strong choice. One of the 15 contenders may surprise you, though: the medical marvel of water with sugar and salt.
The discovery that sugar and salt are absorbed together in the small intestine “was potentially the most important medical advance this century. It opened the way to oral rehydration treatment for severe diarrhea—the main cause of infant death in the developing world.” Simple packets of sugar and salt in the right ratio could be added to water and save the lives of children who were losing electrolytes through severe diarrhea from diseases like cholera. In a hospital or doctor’s office, we’d just hook you up to an IV and give you intravenous rehydration therapy, but that isn’t a possibility for many around the world. Cheap, easy, oral rehydration has saved millions of children’s lives every year, such that UNICEF can put out reports like the one titled One Is Too Many: Ending Child Deaths from Pneumonia and Diarrhoea to help eradicate this problem once and for all. Oral rehydration therapy only costs pennies, too. If only manufacturers could figure out a way to sell salty sugar water for two bucks a bottle… 
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