How Much Sodium & Electrolytes Do You Need? (2026 Guide)
On a normal day you need no extra sodium, so there is nothing to buy. Americans already eat about 3,400 mg a day on average, more than the US limit of 2,300 mg. For exercise under an hour, water is enough. In long, sweaty exercise, an average athlete loses about 1,000 mg of sodium an hour in sweat, but some lose a few hundred and some over 2,000. Most powders hold less than that: the typical label we read gives 180 mg a serving.
By Erin Rose Updated October 13, 2026 How we score
How much, by situation
| Your situation | What to do | Notes |
|---|---|---|
| A normal day | No extra sodium | Nothing to buy. Food already gives most Americans more than the daily limit (FDA). |
| Exercise under an hour | Water | Under an hour, studies show little difference between a sports drink and water (ACSM 1996). |
| Long or hard exercise, heat | A sodium drink can help | Guidelines back sodium drinks here (ACSM 2007). In sweat, an average athlete loses about 1,000 mg of sodium an hour (Baker 2016). That is a loss, not a target: you do not have to replace all of it. Your hourly loss |
| Keto, low-carb or fasting | No set amount | Some people report adding sodium, but no trial has set a dose (Bostock 2020). Ask your doctor first if you take blood pressure or diabetes medicine. Keto and fasting |
| High blood pressure, heart failure, kidney disease, a low-salt diet, or a water pill, ACE inhibitor or ARB | Ask your doctor first | Extra sodium can raise blood pressure (FDA), and these drinks hold potassium too. Details |
| Diagnosed POTS or low blood pressure | Ask your doctor | Your doctor sets salt and fluid targets for you. We give no dose. More |
| Sick with vomiting or diarrhea, or a sick child | Ask a doctor or pediatrician | Sports drinks are not oral rehydration solutions. |
Find your electrolyte target
Pick your situation. It tells you whether you are likely to need a sodium drink at all, and when to ask a doctor instead.
Sodium lost in an hour of sweating
Your hourly loss depends on two things: how much you sweat, and how salty your sweat is. Both vary a lot. In 506 athletes, sweat sodium ran from about 419 to 1,628 mg per liter (18.2 to 70.8 mmol/L), with an average of 826 mg (Baker 2016). Sweat rate ran from 0.26 to 5.73 liters an hour, with an average of 1.21. So an average athlete loses about 1,000 mg of sodium an hour. The sodium figures are estimates from a forearm patch, not whole-body measures. The study’s authors work for the Gatorade Sports Science Institute, part of PepsiCo. Find your row and column below:
| Sweat an hour | Light460 mg/L | Average826 mg/L | Salty1,150 mg/L | Very salty1,610 mg/L |
|---|---|---|---|---|
| 0.5 Llight | 250 | 400 | 600 | 800 |
| 1 Lmoderate | 450 | 850 | 1,150 | 1,600 |
| 1.21 Lthe average | 550 | 1,000 | 1,400 | 1,950 |
| 1.5 Lheavy | 700 | 1,250 | 1,750 | 2,400 |
| 2 Lvery heavy | 900 | 1,650 | 2,300 | 3,200 |
To learn your own sweat rate, weigh yourself before and after an hour of training, with no bathroom break. Each kilogram lost is about a liter of sweat; add back what you drank (ACSM 2007).
How many servings match an hour of sweat?
With our pick, Transparent Labs Hydrate, 2 scoops would match the average athlete’s hourly loss of 1,000 mg. You do not have to replace all of it. Start with one serving, drink to thirst (Hew-Butler 2015), and eat food with salt after a long session. The table shows the same for the other drinks we compare, from each label. SaltStick chews, at 100 mg a serving, are made to top up, not to replace a hard hour.
| Product | Sodium each | Servings |
|---|---|---|
| LMNT Recharge Electrolytes1 stick pack | 1,000 mg | 1 |
| BUBS Naturals Hydrate or Die Electrolytes1 stick pack | 650 mg | 1.5 |
| Transparent Labs Hydrate1 scoop (8 g) | 500 mg | 2 |
| Liquid I.V. Hydration Multiplier1 stick pack | 500 mg | 2 |
| Liquid I.V. Sugar-Free Hydration Multiplier1 stick pack | 500 mg | 2 |
| Thorne Daily Electrolytes1 stick pack (4.37 g) | 480 mg | 2.1 |
| DripDrop ORS Hydration1 stick pack | 330 mg | 3 |
| Nuun Sport Electrolyte Tablets1 tablet | 300 mg | 3.3 |
Is a stronger drink better?
Not overall: lower-strength drinks did best in the review we cite. That 2022 review pooled 28 studies and compared drinks by overall strength, which came mostly from sugar (Rowlands 2022). Lower-strength (hypotonic) drinks kept blood volume up best, beating mid-strength drinks and plain water. The strongest drinks were possibly a little better than the mid-strength ones. Salt is a different question. The review did not test drinks saltier than about 1,150 mg of sodium per liter; within that range, more electrolyte helped keep blood volume up later in exercise. The review had no outside funding. Its lead author was previously paid by two sports-drink makers, Lucozade-Ribena-Suntory and Frucor, to report on weaker drinks.
Don’t overdrink
Don’t drink so much that you gain weight during the event. In the 2002 Boston Marathon, 13% of runners tested had low blood sodium. Weight gain during the race was the strongest factor linked to it, along with racing over 4 hours and very low or high body weight (Almond 2005). A 2015 expert consensus on low blood sodium in exercise advises letting thirst guide how much you drink (Hew-Butler 2015).
Do electrolytes stop cramps?
Two small studies found no clear link to low salt. In a study of Ironman triathletes, those who cramped had blood salt levels slightly lower than those who didn’t, but still normal (Sulzer 2005). Pickle juice shortened a cramp set off in the lab by about 49 seconds. That is too fast for the salt to be absorbed. The researchers think it works through a reflex in the mouth and throat (Miller 2010). Cramps have many causes; see a doctor if they are frequent.
On a normal day, and the daily limit
You don’t need an electrolyte drink on a normal day. Adults need about 1,500 mg of sodium a day (the Adequate Intake, National Academies 2019). Americans already eat about 3,400 mg a day on average, more than the 2,300 mg daily limit (FDA). The American Heart Association’s ideal limit is 1,500 mg a day for most adults, especially people with high blood pressure. One stick of the strongest drinks we score holds 1,000 mg, almost half the limit. People who sweat heavily for hours can need more. If you have high blood pressure, heart failure or other heart disease, or kidney disease, or a doctor told you to limit salt, ask your doctor before a high-sodium drink or extra salt. Extra sodium can raise blood pressure (FDA).
If you have kidney disease, or take an ACE inhibitor, an ARB or a potassium-sparing water pill, ask your doctor before a high-potassium drink as well. These drinks hold potassium, and these conditions and medicines can raise blood potassium.
Sports drinks are not oral rehydration solutions. If you are sick with vomiting or diarrhea, ask a doctor or pharmacist what to drink. For a sick child, ask a pediatrician.
POTS and low blood pressure
Some doctors advise extra salt and fluid for POTS or low blood pressure. That target is set by your doctor, for you. This guide gives no dose for it, and the calculator above does not either. Ask your doctor.
Potassium and magnesium
Sweat holds far less potassium and magnesium than sodium (Baker 2017), so sodium is the mineral a sweat drink needs to replace. Adults need about 3,400 mg of potassium a day (men) or 2,600 mg (women), mostly from food such as fruit, vegetables, beans and milk (National Academies 2019). The drinks we score list 30 to 370 mg of potassium a serving.
Adults need 310 to 420 mg of magnesium a day, mostly from food. From supplements, the upper limit is 350 mg a day (NIH Office of Dietary Supplements). Most electrolyte drinks hold little magnesium. See the magnesium dosage guide.
Keto and fasting
Some people on low-carb diets or fasting add sodium. No trial has set a dose. Insulin makes the kidneys hold on to sodium (DeFronzo 1975), so lower insulin on keto may make the kidneys pass more. People on keto often report tiredness and headache in the first days, called keto flu. That comes from people’s own reports, not a trial (Bostock 2020). Ask your doctor first if you have high blood pressure, heart or kidney disease, or take blood pressure or diabetes medicine.
Reading a powder’s label
Check the sodium first. We read 184 electrolyte powder labels in NIH’s database: the typical serving had 180 mg of sodium, and only 7% had 500 mg or more.
| Item | Value |
|---|---|
| Low quarter of labels (25th percentile) | 101 mg |
| Typical label (median) | 180 mg |
| High quarter of labels (75th percentile) | 270 mg |
| Transparent Labs Hydrate, our pick | 500 mg |
Questions
How much sodium do I need per day?
Most people need no extra. Adults need about 1,500 mg a day (the Adequate Intake, National Academies 2019). The US limit is 2,300 mg, and Americans already eat about 3,400 mg on average (FDA). In long, sweaty exercise, an average athlete loses about 1,000 mg an hour in sweat, but some lose a few hundred and some over 2,000 (Baker 2016). Your hourly loss
Do I actually need an electrolyte drink?
Only for long or hard exercise, heavy sweat or heat (ACSM 2007). Under an hour, studies show little difference between a sports drink and water (ACSM 1996). On a normal day, food already covers your sodium.
How much sodium on keto or while fasting?
No trial has set a dose. Some people on low-carb diets add sodium. Insulin makes the kidneys hold on to sodium (DeFronzo 1975), so lower insulin may make them pass more. Keto flu comes from people’s own reports, not a trial (Bostock 2020). Ask your doctor first if you have high blood pressure, heart failure or kidney disease, or take blood pressure or diabetes medicine. Keto and fasting
Can too many electrolytes be dangerous?
Yes, in two ways. Too much sodium can raise blood pressure (FDA), and one stick of the strongest drinks has 1,000 mg, almost half the daily limit. And drinking too much water in a long event can drive blood sodium dangerously low, called hyponatremia: 13% of Boston Marathon runners tested had it (Almond 2005). Let thirst guide how much you drink (Hew-Butler 2015). If you have high blood pressure, heart failure or kidney disease, or a doctor told you to limit salt, ask your doctor before a high-sodium product. If you have kidney disease or take an ACE inhibitor, an ARB or a potassium-sparing water pill, ask before a high-potassium drink too. Don’t overdrink
More electrolyte guides
- The best electrolyte drink, scored on sodium, testing and cost
- Every formula side by side, and how to make your own
- Gatorade alternatives
- LMNT vs Liquid I.V.
- Liquid I.V. vs Gatorade vs Pedialyte
- What each electrolyte costs per 1,000 mg of sodium
- Magnesium dosage guide
Sources
- Baker LB, et al. Normative data for regional sweat sodium concentration and whole-body sweating rate in athletes. J Sports Sci. 2016. PubMed 26070030
- Sawka MN, et al. ACSM position stand: exercise and fluid replacement. Med Sci Sports Exerc. 2007. PubMed 17277604. Convertino VA, et al. ACSM position stand: exercise and fluid replacement. Med Sci Sports Exerc. 1996. PubMed 9303999
- Rowlands DS, et al. Sports Med. 2022. PubMed 34716905. Almond CS, et al. N Engl J Med. 2005. PubMed 15829535. Hew-Butler T, et al. Statement of the Third International Exercise-Associated Hyponatremia Consensus Development Conference. Clin J Sport Med. 2015. PubMed 26102445
- Sulzer NU, et al. 2005. PubMed 16015122. Miller KC, et al. 2010. PubMed 19997012
- DeFronzo RA, et al. J Clin Invest. 1975. PubMed 1120786. Bostock ECS, et al. Front Nutr. 2020. PubMed 32232045
- Baker LB. Sweating rate and sweat sodium concentration in athletes: a review. Sports Med. 2017. PubMed 28332116
- National Academies of Sciences, Engineering, and Medicine. Dietary Reference Intakes for Sodium and Potassium. 2019. American Heart Association, sodium guidance (ideal limit 1,500 mg a day). NIH Office of Dietary Supplements, magnesium fact sheet.
- FDA, sodium in your diet. Label census: NIH Dietary Supplement Label Database, read September 18, 2026.