Carbohydrates
First, it’s important to know what you should be looking for on the nutritional label. Gabriela Barreto, a registered dietitian and sports nutritionist, says most quality electrolyte brands range from 300 to upwards of 1500 milligrams of sodium. “What research shows for optimal and rapid rehydration is the addition of carbohydrates into the electrolyte mix,” she explains. This is because carbs are more rapidly absorbed into the bloodstream and, as a result, rehydrate your cells more efficiently. Most brands have between 10 to 20 grams of carbs in their formulas. Other ingredients you should look for include magnesium, potassium, calcium and sometimes chloride since they’re all also electrolytes, advises Albarran.
Sodium
Most importantly, you want to focus on sodium because it’s the primary electrolyte lost through sweat. The amount of sodium you will need depends on how much you sweat and how much sodium you lose when you sweat. “The average loss of sodium is 950 mg/liter of sweat, but this can range from 200 to 2000 mg of sodium depending on the person,” explains Barreto.
You can also calculate your sweat rate at home by following this CDC-approved formula. Other methods may include using a sweat patch, but it’s essential to know that some methodologies may provide inconsistent results, so bear in mind these are estimates. The sweat test, which reads the level of chloride in sweat, is the most accurate method when done correctly and in a lab. Generally, children with cystic fibrosis have a sweat test done to get a diagnosis since those with CF have higher levels of chloride in their sweat.
Physical activity
If you are an active gym goer or athlete, you’ll want to make sure you’re prioritizing replenishing electrolytes and carbohydrates. “An indicator of increased electrolyte needs would be cravings post-exercise and/or headaches, muscle cramping, lightheadedness and fatigue,” explains Nairn. “I usually recommend looking for supplements that provide higher amounts of sodium and potassium, which are more readily lost during exercise through sweat.” For athletes, Barreto recommends sticking to electrolytes with 500 to 1000 milligrams of sodium. “Some of the higher sodium brands do not contain carbs, which athletes training longer than one hour will need an alternative carb source for fueling purposes as well,” Barreto advises.
Sugar
If you’re looking to add electrolytes to your water but aren’t generally active, Barreto suggests choosing a sugar-free electrolyte with sodium less than 300 milligrams. “While carbs help with optimal rehydration, that’s more important for heavy sweaters who are actively performing,” she explains. In this case, sugar-free options are suitable for those who don’t exercise but like adding electrolytes to their water. “Those engaging in moderate to intense exercise should avoid sugar-free options because sugar is necessary post-exercise for energy replenishment,” Nairn says.
Pregnancy
Pregnant patients may want to consider paying attention to their electrolyte levels. This can be because of hormonal changes, increased blood volume, morning sickness and higher sweat rates, especially if they are active. If you are pregnant and concerned about your sodium levels, see your healthcare provider.