An electrolyte is a substance that conducts electricity when dissolved in water. Electrolytes, such as sodium and potassium, are essential for a number of functions in the body.

Everyone needs electrolytes to survive. Many automatic processes in the body rely on a small electric current to function, and electrolytes provide this charge.

Electrolytes interact with each other and the cells in the tissues, nerves, and muscles. A balance of different electrolytes is crucial for the body to function.

Fast facts on electrolytes
  • Electrolytes are vital for the healthy functioning of the human body.
  • Fruits and vegetables are good sources of electrolytes.
  • Common electrolytes include sodium, potassium, calcium, and bicarbonate.
  • The symptoms of an electrolyte imbalance can include twitching, weakness, and, if unchecked, seizures and heart rhythm disturbances.
  • Older adults are particularly at risk of an electrolyte imbalance
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Electrolytes are chemicals that conduct electricity when dissolved in water.

They regulate nerve and muscle function, hydrate the body, balance blood acidity and pressure, and help rebuild damaged tissue.

The muscles and neurons are sometimes referred to as the “electric tissues” of the body. They rely on the movement of electrolytes through the fluid inside, outside, or between cells.

The electrolytes in human bodies include:

  • sodium
  • potassium
  • calcium
  • bicarbonate
  • magnesium
  • chloride
  • phosphate

For example, a muscle needs calcium, sodium, and potassium to contract. When these substances become imbalanced, it can lead to either muscle weakness or excessive contraction.

The heart, muscle, and nerve cells use electrolytes to carry electrical impulses to other cells.

The levels of electrolytes in the blood can become too high or too low, leading to an imbalance. Electrolyte levels can change in relation to water levels in the body, as well as other factors.

Important electrolytes, including sodium and potassium, are lost in sweat during exercise. A rapid loss of fluids, such as after a bout of diarrhea or vomiting, can also affect the concentration of electrolytes. In these types of situations, the balance of electrolytes in the body needs to be restored.

The kidneys and several hormones regulate the concentration of each electrolyte. If the level of one is too high, the kidneys filter it from the body, and different hormones act to restore a balance.

An imbalance causes a health issue when the concentration of a certain electrolyte becomes higher than the body can regulate. Low levels of electrolytes can also affect overall health.

The most common imbalances involve sodium and potassium.

Symptoms of an electrolyte imbalance

The symptoms depend on which electrolyte is out of balance and whether its level is too high or too low.

A harmful concentration of magnesium, sodium, potassium, or calcium can produce one or more of the following symptoms:

  • irregular heartbeat
  • weakness
  • twitching and muscle spasms
  • changes in blood pressure
  • excessive tiredness
  • numbness
  • confusion
  • bone disorders
  • nervous system disorders
  • seizures
  • convulsions

For example, a calcium excess can occur in people with breast cancer, lung cancer, or multiple myeloma. This type of excess is often caused by the destruction of bone tissue.

Signs and symptoms of excessive calcium may include:

  • frequent urination
  • constipation
  • nausea
  • stomach pain
  • vomiting
  • irregular heartbeat
  • thirst
  • dry mouth or throat
  • lethargy
  • fatigue
  • moodiness and irritability
  • extreme muscle weakness
  • total loss of appetite
  • confusion
  • coma

As these symptoms can also result from cancer or cancer treatment, it may be difficult to identify high calcium levels as the cause.

There are several possible causes of an electrolyte imbalance, including:

  • low levels of electrolytes and hydration after exercise
  • prolonged periods of vomiting or diarrhea
  • poor diet
  • severe dehydration
  • disruption of the acid-base balance, which is the proportion of acids and alkalis in the body
  • congestive heart failure
  • cancer treatment
  • some other drugs, such as diuretics
  • bulimia
  • kidney disease
  • age, as the kidneys of older adults become less efficient over time

An electrolyte panel is a test that screens for imbalances in the blood. It also measures the acid-base balance and kidney function. This test can help monitor the progress of treatment relating to a known imbalance.

A doctor may include it as part of a routine physical exam, and people often undergo it during a hospital stay or when receiving care in an emergency room, as both acute and chronic illnesses can affect electrolyte levels.

A healthcare professional may also perform this test for someone taking medication known to affect electrolyte concentrations, such as diuretics or angiotensin converting enzyme inhibitors.

The levels of electrolytes in the blood are measured in millimoles per liter (l). If the level of one type of electrolyte is too high or low, the doctor will test regularly until the levels are back to normal.

If there is an acid-base imbalance, the doctor may carry out blood gas tests. These measure the acidity, oxygen, and carbon dioxide levels in a sample of blood from an artery. They also determine the severity of the imbalance and how the person is responding to treatment.

Treating an electrolyte imbalance involves either restoring levels that are too low or reducing concentrations that are too high.

If levels are too high, the treatment depends on the cause of the excess. If the body loses water without losing electrolytes, this can lead to an excess, and the treatment involves an infusion of water and glucose.

Healthcare professionals typically treat low levels by supplementing the needed electrolyte.

The type of treatment will also depend on the severity of the imbalance. It is sometimes safe for a person’s electrolyte levels to be replenished over time without ongoing monitoring.

However, the symptoms of an imbalance can be severe, and a person may need to be hospitalized and monitored during the treatment.

Oral rehydration therapy

Doctors mainly use this to treat an electrolyte shortage alongside dehydration, which tends to follow severe diarrhea.

The World Health Organization (WHO) has approved a solution for oral rehydration therapy that contains:

  • 2.6 grams (g) of sodium chloride
  • 1.5 g of potassium chloride
  • 2.9 g of sodium citrate
  • 13.5 g of glucose

These are dissolved in 1 l of water that the person drinks.

Electrolyte replacement therapy

In more severe cases of an electrolyte shortage, healthcare professionals may administer the electrolyte orally or through an IV drip. An infusion of saltwater solution or compound sodium lactate, for example, can help treat a shortage of sodium.


Some causes of an electrolyte shortage, such as kidney disease, are not preventable. In general, having a well-managed diet can help reduce the risk of low electrolyte levels.

Also, having a moderate amount of a sports drink during or after any kind of exertion or exercise can help limit the effects of losing electrolytes through sweat.

For people who do not need treatment in a hospital, a doctor may recommend dietary changes or supplements to balance electrolyte concentrations.

When levels of an electrolyte are too low, it is important to have foods and drinks that contain high amounts of that electrolyte. Here are some options:

Electrolyte neededSources
Sodiumdill pickles
tomato juices, sauces, and soups
table salt
Chloridetomato juices, sauces, and soups
table salt
Potassiumpotatoes with their skin
plain yogurt
pumpkin seeds
collard greens

It is worth knowing how much of each electrolyte is in a type of food or drink. The Department of Agriculture has a searchable database of nutritional contents.

Supplements are also an option for managing low levels of an electrolyte. For example, older adults often do not consume enough potassium, and treatments with corticosteroids or diuretic medications can also reduce these levels. In this case, potassium tablets can boost the concentration in the blood.

Some sports drinks, gels, and candies can restore levels of electrolytes such as sodium and potassium during and after exercise. They can also help the body retain water.

However, these products sometimes contain high electrolyte contents, and consuming too much can lead to an excess. Some also contain high levels of sugar.

It is important to carefully follow any treatment or supplementation plan that a health professional recommends.

Recommended intake

Restoring the balance of electrolytes by making dietary changes should lead to an improvement in symptoms. If it does not, a doctor may order further tests to identify any underlying health conditions that may be causing the imbalance.

Recommended intakes of some of the most common electrolytes are as follows:

ElectrolyteRecommended intake, in milligrams (mg)Recommended intake for people over 50, in mgRecommended intake for people over 70, in mg
Magnesium420 for men, 320 for women

Electrolytes are a vital part of a person’s chemical makeup. An imbalance can affect the way the body works and lead to a range of symptoms. For example, if a person feels faint after a workout, an electrolyte imbalance could be one reason.

Consuming electrolytes during or after intense exercise and other periods of profuse sweating can help preserve the balance. Be sure to stay hydrated at all times. Anyone with concerns should contact a healthcare professional.