On The Shelf
Mickie Cathers
Many athletes engaging in prolonged or strenuous physical activity, especially in hot weather, swear by electrolyte powders and tablets to improve performance and prevent dehydration-related issues such as cramps or dizziness. While these supplements are popular and generally considered safe to use, they aren’t always necessary and are potentially harmful if overused.
Background
Electrolyte powders and drinks are often used to replenish lost electrolytes such as sodium, potassium, and magnesium due to excess sweating during exercise, illness, or excessive hot weather. Many studies have investigated the impact of electrolyte supplementation on hydration, low sodium levels, and optimizing exercise performance. Though some recent studies are funded by the company that sells the product used in the trial, there are a few protocols without conflicts of interest.
Is there a benefit?
The authors of a randomized controlled trial published in the May 2022 issue of Physiology & Behavior studied the hydration efficiency of electrolyte beverages versus water. Amano and colleagues assessed the blood volume, blood glucose, and lactate concentrations of the participants after consuming water or the electrolyte beverage with sucrose or isomaltulose (an alternative sweetener often used in electrolyte beverages). No differences were observed between participants who drank the electrolyte beverage with sucrose and those who drank water. The results revealed that the electrolyte beverage with isomaltulose demonstrated greater hydration than the other two groups.
Amano and colleagues found similar results in an October 2019 study when they investigated the effects of an electrolyte beverage versus water in maintaining glycemia, rehydration, and attenuating heat loss after moderate-intensity cycling.
Electrolyte packets can aid in rehydration and electrolyte replenishment during episodes of vomiting and diarrhea. Vomiting and diarrhea, common during illnesses, can lead to significant electrolyte loss, especially sodium and potassium.
Electrolyte packets, particularly those rich in sodium, can be helpful for managing symptoms of postural orthostatic tachycardia syndrome (POTS). People with POTS often experience low blood volume, and the sodium in electrolyte packets may help patients retain fluids, increasing blood volume and potentially alleviating symptoms such as dizziness and rapid heart rate.
A placebo-controlled, randomized, double-blind clinical trial by Ly and colleagues published in the November 2023 issue of Nutrients evaluated the effects of sodium and carbohydrates in electrolyte beverages. After three 90-minute interval training sessions, 26 athletes rehydrated with either a high-sodium electrolyte solution (45 mmol Na/L), a low-sodium sports drink (18 mmol Na/L), or water. The study results revealed that within the first hour, the high-sodium electrolyte solution showed significant rehydration compared to water and the low-sodium sports drink. After 3.5 hours, both high- and low-sodium drinks promoted greater hydration than water.
Adverse effects
Excessive consumption of electrolyte supplements can lead to imbalances and potential health issues such as overhydration, elevated BP, GI problems, or kidney dysfunction. Many electrolyte packets are high in sodium with a range of 300 mg to 1,000 mg of sodium per serving. Excess sodium intake can lead to fluid retention and high BP which can strain the kidneys. Common electrolyte imbalances include hypernatremia, hyponatremia, hyperkalemia, hypokalemia, hypermagnesemia, and hypomagnesemia. Maintaining electrolyte balance is essential for healthy kidney function and overdoing it can create or exacerbate kidney problems.
Dosage and availability
Electrolyte supplements are available as powders, tablets, sodas, and popsicles. The powders and tablets are marketed as convenient, on-the-go options for adults and children to be mixed into water. Most of the electrolyte products are available in various fruit and chocolate flavors. Popular brands of electrolyte packets contain between 2 g and 17 g of powder containing up to 17 g of electrolytes and 1,000 mg of sodium.
What to tell your patients
Electrolyte packets can be useful for replenishing lost electrolytes, especially during illness or intense exercise in hot conditions, but it’s important to use them judiciously and be aware of potential risks associated with excessive consumption. Caution patients with high BP or heart issues to be mindful of their sodium intake. A balanced diet and adequate water intake often provide sufficient electrolytes for most people. ■