IN 1965 SCIENTISTS at the University of Florida mixed an unusual cocktail of water, sugar and salt for the college’s American football players. The drink tasted like urine, but the Florida Gators downed it anyway. With lemon juice added for flavour, Gatorade—as the drink was called—was designed to replenish the minerals lost through sweating during hard training sessions in the southern heat. The team reckoned it also boosted their stamina on game day.
Electrolytes are charged particles of minerals such as calcium and potassium that are essential for a healthy body.
Gatorade was an early electrolyte drink, a category of beverage now popular among athletes, gymgoers and schoolchildren. Influencers on social media hawk the stuff as a way for ordinary people to achieve “superior” hydration. But who actually needs it?
Electrolytes are charged particles of minerals such as calcium and potassium that are essential for a healthy body. By creating the voltage differences that drive electrical signals between cells, electrolytes enable everything from muscle movement to body temperature. A healthy diet provides plenty of electrolytes. But as large quantities are lost in sweat, those engaged in intense activity must take pains to replace the lost minerals when they rehydrate. As water alone can dilute the electrolytes in the blood, says Dileep Lobo of the University of Nottingham, electrolyte supplements are sometimes needed.
They offer other benefits, too. A paper published in Nature in 2020 found that the glucose in electrolyte supplements stimulates the absorption of sodium in the gut, making it easier for a dehydrated body to absorb fluid. Supplements may also improve fluid retention and reduce bloating, a potential boon for endurance athletes seeking to reduce bathroom trips.
Illness may be another reason to reach for extra electrolytes. A review published in Health Science Reports in 2022 stressed the effectiveness of electrolyte supplementation in treating diseases involving acute diarrhoea and prolonged vomiting, both of which drain the body of fluid and minerals. Electrolytes can also help cancer patients to cope with treatment. Some of the drugs used in chemotherapy can cause harmful build-up in the kidneys. Electrolytes give those organs a boost in flushing the drugs out of the body.
There is no evidence yet that these supplements offer benefits to the healthy and sedentary majority. What’s more, electrolyte drinks usually come with the sugar, additives and colourings that have been linked with poor health. Sipping electrolytes all day will also overburden the kidneys. Such products offer a one-size-fits-all solution, notes Professor Lobo, even though different bodies may require different concentrations of these minerals.
Too many electrolyte supplements can also be bad for a body’s cells, leading to symptoms such as nausea, headaches and fatigue. Sodium, for example, is a common ingredient in ultra-processed foods, and excesses of it are associated with high blood pressure and weight gain. A normal diet provides sufficient hydration and electrolytes for non-athletes. Fruit and grains are full of potassium. Calcium comes from dairy and greens. Magnesium comes from nuts, legumes and whole grains.
For now, take claims for supplements with a pinch of glucose and salt. PepsiCo, which now owns Gatorade, claims the electrolyte-laden drink is “perfect for all-day, everyday hydration, not just game day”. The science suggests water, most of the time, would be just as good.
