Studies designated to improving the formula led to the redesign of the World Health Organization rehydration solution in 2001 with a lower osmolarity (WHO). These salts are the most effective rehydration method for hangovers, exercise, diarrhea, etc. It's been found that "enteral rehydration is as effective if not better than IV rehydration" enteral being this oral rehydration method (Bellemare et al., 2004; Fonseca, Holdgate, and Craig, 2004).
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