Daily Sodium Target
AHA limit: 1500 mg ideal, 2300 mg max. Athletes lose 500-1500 mg/hr in sweat.
Result
Daily target
3,100 mg
Base 2300 + sweat replacement 800 mg.
- Profile base2300 mg
- Sweat hours1
- Sweat sodium800 mg/L
- Sweat rate1 L/hr
- Sweat sodium loss800 mg
- Daily target3,100 mg
- In salt grams7.9 g salt (40% Na)
Step-by-step
- Sweat loss = hr × mg/L × L/hr = 1 × 800 × 1 = 800 mg.
- Total = base + sweat = 3,100 mg.
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
Blood sodium <135 mmol/L. Causes: drinking only water in long endurance events. Symptoms: nausea, confusion, seizures.
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