How to Replenish Electrolytes—and 6 Signs You May Need To

We don’t have to tell you why it’s important to stay hydrated. You probably already know the sluggish, brain-foggy effects that can come from skimping on water. But what about electrolytes? We’re often told we need to replenish them, especially after a long workout or especially sweaty exercise class—but is that really necessary? And does replenishing electrolytes simply mean chugging a sports drink, or is there more to it? 

Fear not: We’ve got you covered. Read on to learn how to replenish electrolytes (and when you need to), why electrolytes are critical for proper functioning and performance, and how to make sure your body has what it needs with tips and advice from registered dietitians.

What Are Electrolytes and Why Do You Need Them?

“Electrolytes, such as sodium, chloride, potassium, calcium, and magnesium, have many essential roles in the body,” says Mandy Tyler, RD, a sports dietitian nutritionist based in San Antonio. “They’re necessary for regulating fluid balance, helping to transmit nerve impulses, and for normal muscle function.”

To truly understand electrolytes, it helps to have a quick high school chemistry refresher. Electrolytes—minerals that dissolve into water to create charged particles known as ions—are present in almost all fluids and cells in the body. As electrolytes travel in and out of cells, your cells put those electrolytes to work, using them to conduct electrical charges that help regulate a number of processes that keep your entire body functioning. They play a role in just about every vital organ, from your heart to your lungs to your brain. They’re also necessary for muscle contraction, hydration, and fluid balance. 

In short, electrolytes aren’t just some marketing scam. While you may not always need a sports drink to replenish them (more on that later), electrolytes are underrated powerhouses that your body needs to function. Without them, your cells and nerve impulses would stop working properly, leading to a host of problems.  

What Causes an Electrolyte Imbalance?

One of the most noticeable ways we lose electrolytes is through sweat. (It’s electrolytes that make sweat salty!) It makes sense, then, that sweating can lead to the loss of too many electrolytes, triggering an imbalance.

This type of electrolyte imbalance works the other way, too: If your body has too much of a certain mineral, it can throw off the delicate balance of electrolytes to water in your body. (This type of scenario isn’t typically associated with exercise; during an intense workout, you’re usually more likely to lose electrolytes faster than you can replace them.)

All that said, it’s important to acknowledge that people are highly variable in the amount of fluid and electrolytes they lose in sweat, Tyler says. “Some individuals are heavy sweaters, losing a lot of fluid from their body in sweat,” she says. “Others are ‘salty sweaters,’ losing a large amount of sodium in their sweat. Since we are each unique, it’s important for us to be in tune with our individual needs.”

When Do You Need to Replenish Electrolytes?

“If there’s fluid loss, electrolytes and water need to be replaced,” says sports dietitian and certified athletic trainer Dana Angelo White, RDN. While every situation and body is different, there are a few common instances where electrolyte replenishment may be necessary, such as:

Because electrolytes are crucial for your body to properly function, your body will send warning signs that you need to re-up. Common symptoms of electrolyte imbalance include:

How to Replenish Electrolytes

In general, most people consume adequate electrolytes to meet their daily nutrient needs simply by eating a well-balanced diet, Tyler says. “However, in some situations, individuals may lose large amounts of electrolytes within a short period of time, requiring the need to replenish their electrolyte stores,” she adds. This may be the case when, say, you’re running a marathon or completing a triathlon, but usually isn’t the case after a one-hour workout. 

There are numerous ways you can meet your electrolyte needs with food. Since the main electrolyte lost in sweat is sodium, focusing on replacing sodium after a workout will be helpful. “Consuming sodium also helps the body better retain the fluid consumed following activity,” Tyler adds.

But what foods with electrolytes should you start with? “I recommend healthy, higher-sodium foods that offer sodium, chloride, and other nutrients,” White suggests. Her go-to suggestions for electrolyte replenishment include:

But sodium may not be the only electrolyte you’ve depleted during exercise. Potassium is another mineral you’ll want to focus on replenishing, White says. For that, she recommends fruits, veggies, and coconut water, which “offer fluid, fiber, and other nutrients,” she explains. 

And you don’t have to overdo it on these foods either. Just make sure they’re prominent in your regular post-workout meal or snack. And of course, you can load up on water.

What About Sports Drinks?

So do you really need a colorful sports drink to help replace electrolytes? The short answer: It depends. 

While most sports drinks are marketed as a go-to beverage during a workout, they aren’t always necessary. Save them for your longer, more intense exercise sessions or races. 

“Sports drinks get a bad rep, but they are ideal for electrolyte absorption,” White says. “For activities lasting more than 60 minutes, especially in hot and humid conditions, sports drinks before and during activity can be very helpful. Sports drinks vary significantly in their electrolyte content, so it’s important to check labels and choose the best one for your needs.”

How to Keep Electrolyte Levels Balanced In the Future

In healthy people, your electrolyte balance generally takes care of itself with proper hydration and nutrition. But it can help to replenish some fluids and electrolytes as part of good post-workout recovery practices, with the understanding that longer duration and higher intensity exercise will require more, White reiterates. 

“Some people do lose more electrolytes in their sweat than others, so if you experience muscle issues, have an unusually high sweat rate, or experience fatigue during workouts, then additional support from foods, sports drinks, and safe, properly dosed supplements may be necessary,” White says. (Just remember that it’s smart to check in with your doctor or a registered dietitian before starting any new supplements.)

Safety Considerations to Keep in Mind When Replenishing Electrolytes

If you’ve been told to restrict your sodium intake by a doctor, then you should consult with them on how to best meet your fluid and electrolyte needs during activity, Tyler says. “In addition, since the kidney works to maintain electrolyte balance in the body, individuals with kidney disease should also seek guidance from their physician on their individual fluid and electrolyte needs surrounding activity,” she adds. 

And if you do plan to use supplements or tablets (using guidance from a healthcare provider, of course), check labels to determine the type and dose of electrolytes you are consuming, White advises. “Too little or too many electrolytes can be harmful,” she says. “For example, some of the high-dose sodium products on the market could aggravate blood pressure in those who are at risk. If you suspect your electrolytes need evaluation, working with a qualified sports dietitian nutritionist would be your best bet.”

Bottom line: If you have any questions about electrolyte balance, don’t hesitate to talk to a healthcare provider about what you’re experiencing, especially if you have persistent symptoms that you think are linked to electrolyte levels. Your doctor can get to the bottom of what’s going on.  

The Takeaway

Your body needs electrolytes to function but thankfully, in most cases, you don’t need to overthink how you’re going to keep your body well-supplied with these crucial minerals. By focusing on staying hydrated and eating a well-rounded, healthy diet, you’re more than likely meeting your electrolyte needs, even if you exercise daily. But if you’ve been upping the intensity or duration of workouts lately, watch out for signs your electrolytes are low (such as cramps, confusion, fatigue, or headaches) so you can replenish them right away. And most importantly, talk to your doctor about any electrolyte balance questions or concerns. They can figure out what’s going on and provide personalized guidance that’s right for you, your workouts, and your body.

This content is for informational and educational purposes only and does not constitute individualized advice. It is not intended to replace professional medical evaluation, diagnosis, or treatment. Seek the advice of your physician for questions you may have regarding your health or a medical condition. If you are having a medical emergency, call your physician or 911 immediately.