What two nutrients should oral rehydration fluids include?

What two nutrients should oral rehydration fluids include?

• A. K+ and bicarbonate
• B. Calcium and phosphate
• C. NaCl and glucose
• D. Magnesium and sulfate

Answer: (C)

The idea being tested is how oral rehydration works in the gut: water absorption is most effective when sodium is present and glucose is included to drive its uptake. Including sodium (from NaCl) provides the essential electrolyte lost in dehydration and sets up the normal volume and electrolyte balance. The glucose enables sodium and water to be absorbed together through the sodium-glucose co-transport system (SGLT1) in the intestinal lining, so fluids are drawn into the body more efficiently than with saline alone or plain water. Chloride from NaCl helps maintain electroneutrality and replace chloride losses. Other mineral pairings don’t support this key absorption mechanism. They may help with specific electrolyte or acid–base needs in certain situations, but they don’t optimize water uptake via the sodium-glucose transport pathway the way sodium and glucose do.

The idea being tested is how oral rehydration works in the gut: water absorption is most effective when sodium is present and glucose is included to drive its uptake.

Including sodium (from NaCl) provides the essential electrolyte lost in dehydration and sets up the normal volume and electrolyte balance. The glucose enables sodium and water to be absorbed together through the sodium-glucose co-transport system (SGLT1) in the intestinal lining, so fluids are drawn into the body more efficiently than with saline alone or plain water. Chloride from NaCl helps maintain electroneutrality and replace chloride losses.

Other mineral pairings don’t support this key absorption mechanism. They may help with specific electrolyte or acid–base needs in certain situations, but they don’t optimize water uptake via the sodium-glucose transport pathway the way sodium and glucose do.