What Are Electrolytes?

Table of Contents
View All
Table of Contents

Electrolytes are minerals that carry an electrical charge. They play a vital role in the human body, affecting everything from heartbeat to muscle contraction. Electrolyte levels that are too high or too low can cause health problems.

This article discusses the role of electrolytes in health, electrolyte imbalance, and supplementation.

Woman drinking sports beverage

KTStock / Getty Images

What Are Electrolytes?

On a molecular level, electrolytes are chemical substances that have a positive or negative electrical charge when dissolved in water. Because of this, they are able to conduct electricity. When not dissolved, electrolytes are found in a salt form, which has a neutral charge.

Electrolytes are obtained in the diet through various foods. Most water is not chemically pure and contains trace levels of electrolytes.

Vital Body Functions Maintained by Electrolytes

Electrolytes are involved in practically everything your body does. They are present in blood plasma and inside cells, where they help to stabilize cell membranes.

Electrolytes also maintain protein structure and fluid balance. Electrolytes play a role in chemical reactions in the body, and they help transport substances into and out of cells.

Some bodily processes that rely on electrolytes include:

  • Conduction of heartbeat and contraction of heart muscle
  • Dilation and contraction of blood vessels
  • Conduction of nerve impulses
  • Contraction of muscles
  • Filtration in the kidneys
  • Gastrointestinal movement
  • Maintaining proper hydration
  • Maintaining internal pH levels (keeping a proper acid-base balance)

List of Electrolytes in the Human Body

The following electrolytes have important function in the body:

Electrolyte Imbalance

The body keeps electrolytes at optimal levels by regulating absorption in the gastrointestinal tract and excretion in the urine and stool. Problems with intake, absorption, or excretion of electrolytes can lead to imbalance, which can cause a range of symptoms.

Levels of electrolytes can be measured by simple blood tests. High levels of electrolytes are denoted by the prefix "hyper." For example, hypercalcemia means calcium levels in the blood are elevated. The prefix "hypo" indicates low levels of electrolytes, so hypokalemia means potassium levels in the blood are low.

Causes of Electrolyte Imbalance

Electrolyte levels that are too high or too low can have several causes, including:

  • Low intake: A diet with insufficient nutrients can lead to electrolyte deficiency.
  • Fluid losses: Diarrhea and vomiting can lead to low electrolyte levels.
  • Certain medications: Diuretics can cause electrolyte loss in the urine and stool.
  • Kidney disease: The kidneys play a large role in managing electrolyte levels, and levels can be affected by kidney disease.
  • High acidity in the blood: In an attempt to compensate for acidosis (too much acid in body fluids) the kidneys reabsorb bicarbonate.

Symptoms of Electrolyte Imbalance

Symptoms of electrolyte imbalance vary depending on which electrolyte is affected and whether levels are too high or too low. Some of the more common electrolyte imbalances are discussed below.

Sodium Imbalance

Hyponatremia, or low sodium level in the blood, is the most common electrolyte disturbance. It can have many causes, including:

Hyponatremia can cause swelling in the brain. Symptoms of hyponatremia include:

Hypernatremia refers to excessive levels of sodium in the blood. Most often, high sodium levels are seen in elderly people who are not drinking enough water. Infants can also be affected. Symptoms include dry mouth, thirst, fatigue, agitation, and confusion.

Potassium Imbalance

Hypokalemia, or low potassium levels in the blood, can occur with fluid losses, low intake, or when potassium shifts inside of cells. This shift can happen for several reasons, including high blood pH (alkalosis) in the blood and certain medications.

Diuretics are a common cause of hypokalemia. Hypokalemia can cause:

  • Muscle cramping or weakness
  • Constipation (difficulty passing stool)
  • Arrhythmia (irregular or abnormal heart rhythm)

Elevated potassium level is a common problem in people with kidney disease, and can occur with low blood pH (acidosis) and medications. ACE inhibitors (angiotensin converting enzyme inhibitors), a commonly prescribed class of blood pressure medication, can cause hyperkalemia.

Elevated potassium may not cause any symptoms, but can lead to serious arrhythmias.

Calcium Imbalance

Hypocalcemia can be caused by low levels of parathyroid hormone, vitamin D deficiency, and certain medications. Symptoms include:

  • Fatigue
  • Numbness and tingling
  • Muscle cramps
  • Arrhythmias
  • Seizures (when severe)

Hypercalcemia is commonly caused by hyperparathyroidism, a condition in which the parathyroid glands make too much parathyroid hormone (excreted from four glands in the neck, behind the thyroid).

Cancer is another common cause of high calcium levels. Symptoms include:

Magnesium Imbalance

Hypomagnesemia causes include common medications like diuretics, laxatives, and stomach acid lowering medication called proton pump inhibitors. Symptoms are similar to other electrolyte disturbances, such as fatigue and gastrointestinal symptoms.

Hypermagnesemia is less common and typically occurs in people with kidney disease who take magnesium-containing medications. Symptoms include:

  • Weakness
  • Exaggerated reflexes
  • Low blood pressure
  • Muscle weakness
  • Heart rhythm abnormalities

Monitoring and Treating Electrolyte Imbalance

Monitoring

Not everyone requires electrolyte monitoring, but if you have certain conditions or take certain medications, your healthcare provider can monitor electrolyte levels with a simple blood test.

Electrolyte Testing

The basic metabolic panel includes sodium, potassium, chloride, bicarbonate, and calcium. Magnesium and phosphorus can also be measured by separate blood tests.

Treatment Overview

The priority of treatment should be correcting the underlying cause of electrolyte imbalance. Supplementation may be required for managing low electrolyte levels. Treatment includes:

  • Oral rehydration therapy is a special liquid preparation that contains electrolytes and sugar. It can be helpful in situations of excessive electrolyte loss from dehydration. Pedialyte is an example of oral rehydration therapy that can be purchased at a pharmacy.
  • Electrolyte replacement therapy can also be given for supplementation. Some electrolyte supplements, like those containing magnesium and calcium, can be purchased over the counter, without a prescription. Others, like potassium chloride, require a prescription.

Prevention

For most people, eating a varied diet and staying hydrated are all you need to do to maintain electrolyte balance.

People who have kidney disease and are prone to elevated electrolyte levels (such as potassium and phosphate) should follow a special diet that limits these nutrients. They may also require medication called phosphate binders.

Those experiencing high levels of electrolyte loss through gastrointestinal fluid losses or severe exertion with excessive sweating should take care to stay hydrated and consume beverages that contain electrolytes. Be mindful of the high sugar content in most beverages marketed for this purpose.

Sources of Electrolytes

Foods With Electrolytes

Some healthy sources of electrolytes include:

  • Fruits like bananas, watermelon, and lemons
  • Vegetables like leafy greens and avocados
  • Whole grains
  • Nuts and beans

Drinks With Electrolytes

Drinks that contain electrolytes include:

  • Coconut water
  • Milk
  • Fruit juices and smoothies

Marketed Sports Drinks

Sports drinks like Gatorade and Powerade also contain electrolytes and were designed for electrolyte replacement for athletes experiencing excessive electrolyte loss through sweating. However, these beverages often have high amounts of sugar.

Recommended Intake

Recommended intake for various electrolytes according to U.S. Department of Agriculture (USDA) guidelines is shown below. Note that ranges are given, and exact recommendations depend on age and sex.

  • Potassium: 2,600–3,400 milligrams
  • Sodium: 2,300 milligrams (note that the American Heart Association recommends 1,500 milligrams per day)
  • Phosphorus: 700 milligrams
  • Calcium: 1,000–1,200 milligrams
  • Magnesium: 310–420 milligrams

Should I Supplement My Diet With Electrolytes?

Most people do not require electrolyte supplementation. By eating a nutritious diet and staying hydrated with water you should get sufficient electrolytes.

During times of excessive fluid loss (through diarrhea, vomiting, or excessive sweating), oral rehydration solutions can be used.

People with medical conditions and those who take certain medications that alter electrolyte balance may be prescribed electrolyte supplements, but this should always be monitored by a healthcare provider.

Summary

Electrolytes are a vital for the function of your organ systems. Having levels that are too high or too low can cause problems. The best way to maintain normal electrolyte levels is by eating a healthy and varied diet that includes fruits and vegetables, avoiding excessive intake of any one type of food or nutrient, and staying hydrated.

A Word From Verywell

Most people don't need to pay much attention to electrolyte levels and can maintain healthy levels with a nutritious diet and adequate hydration. Taking electrolyte supplements can be problematic because beverages that market themselves for electrolyte repletion often are filled with sugar. And taking over-the-counter supplements can be unnecessary, costly, and even lead to side effects from elevated levels. The best way to maintain electrolyte levels is to eat a nutritious diet and stay hydrated.

Frequently Asked Questions

  • What is a good source of electrolytes?

    Electrolytes are found in a variety of foods and drinks. Fruits, colorful vegetables, beans, and nuts are all healthy sources of electrolytes. Beverages like coconut water and fruit smoothies also provide electrolytes.

  • What are the main electrolytes?

    The most important electrolytes found in the highest amounts in the body are sodium, potassium, chloride, bicarbonate, chloride, calcium, phosphate, and magnesium.

  • What is the best way to replenish electrolytes?

    Most people get sufficient electrolytes in their diet. For situations with high levels of electrolyte loss, such as gastrointestinal illness and excessive sweating, electrolyte replenishment can be achieved with an oral rehydration solution, such as Pedialyte. Be aware that sports drinks have a lot of electrolytes but are often filled with sugar, which can make diarrhea worse.

  • Does lemon water have electrolytes?

    Lemon water does have electrolytes and is a good source of potassium. According to the USDA, juice from one lemon contains approximately 48 milligrams of potassium, 3 milligrams of calcium, 3 milligrams of magnesium, 4 milligrams of phosphorus, and less than 1 milligram of sodium.

  • Is milk good for electrolytes?

    Milk is a good source of electrolytes. According to the USDA, 1 cup of whole milk contains about 305 milligrams of calcium, 30 milligrams of magnesium, 250 milligrams of phosphorus, 375 milligrams of potassium, and 95 milligrams of sodium.

  • Does apple cider vinegar have electrolytes?

    Apple cider vinegar is another good source of potassium. 1 tablespoon of Bragg's organic apple cider vinegar has 11 milligrams of potassium.

7 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. NIH National Library of Medicine. Fluid and electrolyte balance.

  2. Roswell Park Cancer Center. Electrolytes: what are they? What happens when you don't have enough?.

  3. Gankam K, Decaux G. Hyponatremia and the brainKidney International Reports. 2018;3(1):24-35. doi:10.1016/j.ekir.2017.08.015

  4. Kardalas E, Paschou S, et al. Hypokalemia: a clinical updateEndocrine Connections. 2018;7(4):R135-R146. doi:10.1530/EC-18-0109

  5. USDA. Dietary guidelines for Americans 2020-2025.

  6. American Heart Association. Shaking the salt habit to lower blood pressure.

  7. USDA. FoodData central.

By Angela Ryan Lee, MD
Angela Ryan Lee, MD, is board-certified in cardiovascular diseases and internal medicine. She is a fellow of the American College of Cardiology and holds board certifications from the American Society of Nuclear Cardiology and the National Board of Echocardiography. She completed undergraduate studies at the University of Virginia with a B.S. in Biology, medical school at Jefferson Medical College, and internal medicine residency and cardiovascular diseases fellowship at the George Washington University Hospital. Her professional interests include preventive cardiology, medical journalism, and health policy.