Electrolytes: A Complete Guide

Have you ever seen an advertisement for a commercial sports drink and wondered what it is about those drinks that makes them so popular? For many people, sports drinks are just something they consume after a workout or a game without giving a second thought to the chemistry and science behind the formula. In fact, sports drinks are just one form of supplements that are designed to replace electrolytes and restore hydration to the body. Understanding what electrolytes are and how they work is key to helping you make an informed decision about how best to replace electrolytes, because there are many more options these days than sports drinks packed with carbohydrates, calories, and sugar. Consider this your complete guide to understanding electrolytes. 

What are electrolytes?

Electrolytes are minerals in the body that carry a positive or negative charge and conduct electricity when dissolved in water. As noted previously, electrolytes are most commonly associated with commercial sports drinks, but we get most of the electrolytes we need from natural sources like different foods. Electrolytes play a major role in maintaining proper function inf the body, and they are primarily found in your sweat, blood and urine. The body counts on electrolytes to perform a number of significant functions, including: 

  • Muscle function
  • Proper hydration
  • Nervous system function
  • Balancing internal pH levels

There are seven different electrolytes found in the human body, including sodium, potassium, magnesium, chloride, calcium, phosphate, and bicarbonate; however, sodium, potassium, and magnesium are considered the three major electrolytes. 


Sodium is found in large quantities in the body, and it plays a major role in maintaining the balance of fluids internally. In addition to being critical for proper hydration, sodium also plays a critical role in maintaining proper function of the muscles and nerves. Western diets are often high in sodium from processed foods, so most people do not need to replace sodium in significant amounts through electrolyte supplements. Sodium is most commonly lost through urine and sweat, and the kidneys are responsible for adjusting the amount of sodium that is expelled through the urine based on fluid levels in the body. 


Potassium is another of the most common minerals in the body, with approximately 80 percent stored in the cells of the muscles and an additional 20 percent stored in the cells of the liver, bones, and red blood cells. From its location within the cells of the muscles, you may have guessed that potassium plays a significant role in regulating muscle contractions, as well as maintaining a proper balance of fluids in the body and sending and receiving nerve signals. Most Americans do not take in enough potassium from their daily diets, but imbalances most commonly occur as a result of chronic vomiting or diarrhea.  


Magnesium is involved in more than 600 cellular reactions and is another of the most common minerals in the body. However, more than two thirds of Americans do not meet the recommended daily intake guidelines for magnesium in their diets. The body requires magnesium in order to help make DNA, maintain healthy brain function, support a healthy, regular heartbeat, regulate muscle contractions, and perform many other functions. When the body has too little magnesium, cells in the brain, heart, and muscles may become overstimulated, potentially causing permanent damage.  As a result, it is important to replace any lost magnesium in order to prevent a deficiency. 

What do electrolyte supplements do?

Electrolyte supplements are important tools that can help prevent dehydration by replacing the electrolytes that we lose while performing normal activities each day, such as working out or spending time in the sun. While electrolyte supplements are most well known for their use during a sports game or after a workout,there are many other helpful applications for electrolyte supplements that have nothing to do with athletics. Because electrolytes play such an important role in maintaining the overall health of the body, including maintaining brain health and function, electrolyte supplements can help ensure that you feel your best by preventing electrolyte imbalances. When people receive enough electrolytes, they are more likely to have the energy they need to concentrate and perform cognitive tasks well, which can help improve performance at work and on the field. If you’ve gone out for a big night and are experiencing a hangover, electrolyte supplements can also help to relieve hangover symptoms by reversing dehydration, reducing the pain from a headache, minimizing feelings of fatigue, reducing nausea, and minimizing muscle and joint pain.  An estimated 75 percent of Americans are chronically dehydrated, so electrolyte supplements have useful applications for nearly everyone.

What are the signs of dehydration?

The body becomes dehydrated when fluid stores are too low to perform essential functions as a result of losing more water or fluid than is taken in. Older adults and young children are the most likely to experience dehydration, but dehydration can happen to anyone regardless of age. Although conventional wisdom says to drink water when you’re thirsty, thirst is actually a sign of significant dehydration instead of early dehydration. Therefore, staying hydrated requires regular fluid intake even when you’re not thirsty. Common signs of dehydration include:

  • Dry mouth
  • Diminished urine input
  • Lightheadedness
  • Headache
  • Dizziness
  • Dark yellow urine
  • Tiredness

When dehydration reaches severe levels, it can be very dangerous. Signs of severe dehydration include:

  • Drop in blood pressure
  • Shock
  • Seizure
  • Reduced elasticity of the skin
  • Confusion
  • Coma
  • Quickening heart rate
  • Fever
  • Lethargy
  • Sunken eyes

If rehydration does not occur, dehydration can cause death. However, it is possible to prevent dehydration by taking in enough fluids and also replenishing the stores of electrolytes in the body in order to prevent an electrolyte imbalance. While water alone can be enough to rehydrate the body on a normal basis or after short bouts of activity, it is often not enough to rehydrate after a tough workout, big night out, or long day spent in the sun. In fact, drinking too much water without replacing electrolytes can lead to a dangerous condition called hyponatremia, which is a severe sodium imbalance. Hyponatremia can be fatal, which is why it is so important to replace the electrolytes expelled by the body with an electrolyte supplement that can help restore balance to levels of electrolytes and fluids in the body. 

When should you use electrolyte supplements?

If you think that the only time you should use electrolyte supplements is after a hard workout, you might be surprised to know that electrolyte supplements can also be beneficial at other times. While people used to receive plenty of electrolytes from their water sources, most water available today is highly overpurified, which strips beneficial vitamins and minerals, including electrolytes, from the water. As a result, it’s possible to suffer from dehydration even if you drink plenty of fluids because an electrolyte imbalance can still occur. People can use electrolyte supplements to help provide an energy boost and improved concentration during the workday, help reduce hangover symptoms that many people experience after a big night out, or reduce recovery times if you are fighting off an illness. Electrolyte supplements should also be used by people who work outdoors in hot conditions, as dehydration is common when you’re working under the hot sun. Electrolyte supplements that do not contain calories, sugar, or carbohydrates can be useful after a workout of any length. 

How should you take electrolyte supplements and how much do you need?

Commercial sports drinks and electrolyte supplements are often packed with calories, carbohydrates, and sugar that you don’t need in order to correct electrolyte imbalances and prevent dehydration. Unless you’re an endurance athlete, you do not need to ingest carbohydrates, sugar, or calories during a standard workout. Therefore, electrolyte supplements that come in the forms of capsules and concentrates with no carbs, sugar, or calories are the best solution for most people. These supplements will still replenish electrolytes that are lost via sweat and help avoid dehydration while also supporting muscle gain and recovery, reducing the risk of heat stress, and minimizing cramps and joint pain. Although the amount of electrolytes needed will vary depending on how much you sweat and your specific situation, the Institute of Medicine provides general daily intake recommendations for electrolytes. A daily intake of 2,000 mg or less of sodium is recommended, as well as 4,700 mg of potassium and 330-350 mg per day of magnesium for men and 255-265 mg per day for women.