Daily Sodium Target
AHA limit: 1500 mg ideal, 2300 mg max. Athletes lose 500-1500 mg/hr in sweat.
Result
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How to use this calculator
- Pick profile.
- For athletes: enter sweat hours + sodium concentration + rate.
About this calculator
Sodium needs vary widely by activity. FDA limit: 2300 mg/day for healthy adults. AHA ideal: 1500 mg. Salt-sensitive: 1500 mg. Endurance athletes lose 500-1500+ mg per hour in sweat — under-replenishment causes hyponatremia (low blood sodium, dangerous in marathons). Salt = 40% sodium by mass. 1 g salt = 400 mg sodium. Sources: FDA, AHA, ACSM 2007 position stand.
Frequently asked
Hyponatremia?+
Blood sodium <135 mmol/L. Causes: drinking only water in long endurance events. Symptoms: nausea, confusion, seizures.
Salty sweater?+
Some people lose 1500+ mg sodium per liter sweat (vs. avg 600-800). Look for white salt rings on shirt.
Best sodium sources?+
Sports drinks (Gatorade endurance: 300 mg/12oz), salt tabs (200-500 mg each), pretzels, pickles.
Salt vs. sodium?+
Salt = NaCl. 40% sodium by mass. 2300 mg sodium = ~5.75 g salt = ~1 tsp.
Low-sodium diet harm?+
Below 1500 mg in active people: dehydration, cramps, low BP. Below 1200 mg: hyponatremia risk even sedentary.
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