Electrolyte powders

Are electrolyte powders safe?

For most healthy adults, yes. An electrolyte powder is mostly salt, some potassium and magnesium, and often sugar or a sweetener. Healthy kidneys clear what the body does not need. The honest catch is that most people drinking them every day do not need them, and the doses are not small. One popular zero-sugar stick holds 1,000 mg of sodium, 200 mg of potassium and 60 mg of magnesium; many sugar-based sticks give about 500 mg of sodium with around 11 g of added sugar.

Social media turned these products from an endurance-sport niche into an all-day habit, sold for energy, skin and focus. A 2025 note from dietitians at Hackensack Meridian Health put it plainly: for most people in a heatwave, water is the best way to stay hydrated. Electrolyte powders earn their place in long, hot, sweaty exercise and in illness with vomiting or diarrhoea. Outside that, they mostly add salt and sugar.

How much sodium and potassium is too much?

There is no upper limit for sodium, because the US National Academy of Medicine found no clear toxic threshold. What it set instead is a chronic disease risk reduction level of 2,300 mg a day for adults, the point above which blood pressure and heart risk rise. The average diet already exceeds it. A 1,000 mg stick is over 40% of that figure; two or three sticks a day on top of normal meals is a lot of salt for anyone with high blood pressure.

Potassium is safe for people with healthy kidneys at these amounts. The Linus Pauling Institute notes that the kidneys adjust excretion to intake, and severe high potassium (hyperkalaemia) needs very large single doses in healthy people. The picture changes with kidney disease or certain medicines (see below), where potassium can build up and cause dangerous heart rhythms.

Hyponatraemia and hypernatraemia: the two salt problems

Many people buy electrolytes to avoid hyponatraemia, low blood sodium. That is the right worry for the wrong reason. The third international consensus on exercise-associated hyponatraemia (British Journal of Sports Medicine, 2015) concluded that the main cause, and the cause of all known deaths, is drinking more fluid than the body loses. At least 14 athletes have died since 1981. Sports drinks hold 10 to 38 mmol/L of sodium against about 140 mmol/L in blood, so drinking them in excess still dilutes the blood. The panel's advice: drink to thirst; extra sodium helps a little only when fluid intake roughly matches sweat losses.

Hypernatraemia, high blood sodium, is rarer. The Linus Pauling Institute says it seldom comes from salt intake and usually follows water loss. The practical risk is mixing a stick in less water than the label says, or giving concentrated drinks to small children who cannot ask for water.

The 2011 South African Medical Journal series on four ultramarathon runners with kidney failure is a reminder that context matters: all four had used the same anti-cramp electrolyte supplement, but all had also taken painkillers, three of them NSAIDs, and the amounts of electrolytes were within daily limits.

Kidney disease and medicines

People with chronic kidney disease should not use electrolyte powders without advice. Their kidneys may not clear potassium, and extra sodium worsens fluid retention and blood pressure.

The Linus Pauling Institute lists medicines that raise the risk of high potassium when combined with supplemental potassium: ACE inhibitors such as lisinopril, angiotensin receptor blockers such as losartan, potassium-sparing diuretics such as spironolactone, trimethoprim and NSAIDs such as ibuprofen. If you take any of these, or have heart failure or kidney disease, talk to your doctor or pharmacist before using an electrolyte product. Our potassium page covers the mineral in more detail.

Children

Electrolyte sticks are made for adults. The American Academy of Pediatrics warned in 2011 that frequent sugary sports drinks raise the risk of overweight and obesity in children and teenagers, and an 11 g sugar stick daily adds up. For a child with diarrhoea or vomiting, the right product is an oral rehydration solution, whose composition is set for that job: the WHO formula has 75 mmol/L sodium, 20 mmol/L potassium and 75 mmol/L glucose. Ask a pharmacist which one to use, and see a doctor quickly for babies.

Product quality

Problems found so far are mostly manufacturing slips. FDA enforcement records include a 2024 recall of an "Electrolytes" flavour that actually contained caffeine, a 2024 recall of electrolyte drink powder for possible metal fragments, and a 2022 recall of a children's rehydration powder made with an undeclared wheat-derived ingredient. Some consumer advocates have reported lead in unflavoured powders, but no peer-reviewed survey of electrolyte powders has been published, so the extent is unknown. Products certified by NSF Certified for SportThird-party testingTesting of a supplement by an independent lab to check that it contains what the label says and is free of set contaminants.More in the glossary or Informed Sport are tested for banned substances and some contaminants.

How to use them sensibly

1. Save them for long or hot exercise (more than about an hour of heavy sweating), or illness with fluid loss.
2. Read the sodium figure and count it toward 2,300 mg a day.
3. Mix with the stated amount of water, never less.
4. Do not use them to justify drinking more than you are thirsty for during endurance events.
5. Check first if you have kidney or heart disease or take blood pressure medicines.

How we scored it

Regulatory actions (85) are strong, with only minor recalls. Dose safety (72) and organ toxicity (75) reflect high sodium per stick and potassium risk in kidney disease rather than harm in healthy users. Interactions (68) are the weakest factor because so many common blood pressure drugs raise potassium. Quality (72) is held back by recalls and the lack of independent metal testing. The score sits close to potassium and well above pre-workout.