The long-endurance athletic community is likely familiar with electrolytes and their ability to enhance exercise performance. Otherwise, they are often misunderstood. 

In fact, electrolytes help the body regulate many key metabolic reactions, maintain fluid, pH and so much more. They are also found well beyond infamous sports drinks! 

This article shines light on prominent electrolyte functions and imbalances and covers the best sources of these powerful minerals. Take a look!

What Are Electrolytes?

In the chemistry world, electrolytes refer to any particle that carries a positive or negative electrical charge. Cations have a positive charge whereas anions hold a negative charge.

In the nutrition sphere, electrolytes encompass essential minerals found in blood, sweat, urine, and cells. When these essential minerals dissolve in water, they form electrolytes and become important electrically charged ions that drive numerous metabolic processes. Their key functions rely on electricity derived from opposite electrical charges.

Generally speaking, electrolytes are found in every cell in the body. They aid nerve, muscle, and blood pressure function and help maintain fluid and acid-base (pH) balance. 

The main electrolytes found in the body include:

• Sodium
• Potassium
• Chloride
• Calcium
• Magnesium
• Phosphate
• Bicarbonate

Electrolyte Recommendations

Electrolytes are considered essential, meaning humans need to consume (most of) them from the diet. The kidneys then filter extra electrolytes, which are lost in urine and sweat.

The daily requirement recommendation for electrolytes depends on age, activity level, water intake, and climate. Most people naturally obtain enough electrolytes from common foods and beverages. Many athletes make a concerted effort to acquire additional electrolytes through sports drinks.

Those who regularly exercise in a hot environment, sweat a lot, or vigorously work out for longer than an hour may need more electrolytes right before, during, or after activity. 

Furthermore, those with diarrhea or vomiting may also temporarily need extra electrolytes, since they are rapidly lost when a large amount of fluid is excreted. 

Sources of Electrolytes

Although electrolyte drinks and packages are all the rage right now, numerous whole foods contain meaningful levels of electrolytes. When talking about electrolyte consumption, we are mostly focused on: 

• Sodium
• Potassium
• Magnesium
• Calcium

Chloride is often added to sports drinks but phosphate and bicarbonate are not naturally found in foods. Instead, they are instead created by the body elsewhere.

Moreover, because electrolytes require water to function properly, plant foods, especially fruits and vegetables which have high water content are typically the best sources of electrolytes. Food sources of electrolytes include the following:

High Sodium Foods

• Himalayan or Celtic sea salt
• Table salt (chloride too)
• Pickles and pickled foods
• Salted nuts
• Smoked salmon
• Deli/cured meats
• Snacks like crackers, chips, and pretzels
• Seaweed

High Potassium Foods

• Potatoes
• Broccoli
• Bananas
• Leafy greens
• Citrus fruits
• Avocado
• Zucchini
• Mushrooms
• Halibut, cod, tuna
• legumes

High Calcium Foods

• Dairy
• Almonds
• Broccoli
• Fortified cereals and some milks (soy)
• Spinach
• Kale
• Chia seeds
• Sardines
• Canned salmon
• Edamame
• Dried figs

High Magnesium Foods

• Spinach
• Nuts (almonds, cashews, brazil)
• Seeds (pumpkin, chia, flax)
• Whole grains
• Peanuts and peanut butter
• Dark chocolate
• Avocados
• Legumes
• Tofu
• Salmon, mackerel, halibut
• Bananas

What Do Electrolytes Do?

At the most basic level, electrolytes help keep the body balanced or in homeostasis by conducting electricity in the water. The electrically charged ions produce electricity while the water in fluids facilitates the exchange of electricity. 

While each of the seven types of electrolytes contributes to various different metabolic processes, the main functions of electrolytes include:

• Regulate fluids inside and outside of cells
• Balance fluid levels in blood plasma
• Transmit nerve signals to and from the heart, muscle, and nerve cells to other cells
• Build new tissue
• Support blood clotting
• Stimulate muscle contractions (including the heart)
• Maintain blood pH level (acid-base balance)

The main body functions of each electrolyte include:

Sodium

• Controls fluid balance
• Impacts blood pressure
• Helps with muscle contraction
• Spurs nerve impulses

Chloride

• Helps overall electrolyte balance
• Balances acids and bases (pH)
• Required for adequate digestion

Potassium

• Regulates heart and blood pressure
• Transmits nerve impulses
• Aids bone health
• Helps with muscle contraction

Magnesium

• Helps produce DNA and RNA
• Transmits nerve impulses
• Helps with muscle contraction
• Maintains heart rhythm
• Regulates blood sugar levels
• Enhances the immune system

Calcium

• Bone and teeth turnover, growth, and maintenance
• Transmits nerve impulses
• Helps with muscle contraction
• Contributes to blood clotting

Bicarbonate

• Balances acids and bases (pH)
• Regulates heart function

Phosphate

• Strengthens bone and teeth
• Helps cells produce energy for tissue growth and repair

What Causes Electrolyte Imbalances?

Electrolytes not only help with fluid balance but also rely heavily on the maintenance of fluid balance to function properly. Thus, the majority of electrolyte imbalances are related to a rapid and/or chronic loss of fluids through:

• Extreme sweating
• Vomiting
• Diarrhea
• Excessive urination. 

Certain medications can deplete electrolytes. Some conditions like kidney disease, severe burns, and eating disorders can also lead to electrolyte imbalances.

In general, elevated electrolyte levels are indicated by the prefix "hyper." Low levels of electrolytes are designated by "hypo."

For example, a calcium imbalance is called hypercalcemia or hypocalcemia while a potassium imbalance is called hyperkalemia or hypokalemia. The latter is because potassium is abbreviated K+ on the periodic table of elements in chemistry. 

Mild electrolyte imbalances rarely cause side effects but symptoms of more significant electrolyte imbalances include:

• Fatigue
• Muscle cramping
• Headaches
• Nausea or vomiting
• Abdominal cramping and diarrhea
• Fluid retention
• Fast or irregular heartbeats
• Numbness or tingling
• Confusion
• Irritability
• Convulsions and seizures

Severe electrolyte imbalances can be life-threatening, so it is important to seek medical help immediately. 

The most common causes of each electrolyte imbalance are as follows.

Sodium

Hypernatremia

• Dehydration
• Low water consumption
• Excessive fluid losses (sweating, vomiting, diarrhea)
• Medications like corticosteroids

Hyponatremia

• Excessive fluid loss
• Vomiting and diarrhea
• Alcoholism
• Overhydration/consuming too much water in proportion to sodium
• Thyroid, hypothalamic and adrenal disorders
• Liver, heart, or kidney failure
• Medications like diuretics and antiepileptics

Potassium

Hyperkalemia

• Severe dehydration
• Kidney failure
• Ketoacidosis (uncontrolled diabetes)
• Medications like blood pressure and diuretics
• Adrenal insufficiency

Hypokalemia

• Eating disorders (especially bulimia and purging disorder)
• Severe vomiting and diarrhea
• Dehydration
• Medications like laxatives, diuretics, and corticosteroids

Chloride

Hyperchloremia

• Severe dehydration
• Kidney failure
• Dialysis

Hypochloremia

• Cystic fibrosis
• Eating disorders (especially anorexia nervosa)
• Acute kidney failure
• Scorpion stings

Calcium

Hypercalcemia

• Kidney disease
• Thyroid disorders
• Lung disease
• Some cancers (especially lung and breast)
• Excessive antacid use
• Medications like lithium, theophylline, diuretics

Hypocalcemia

• Kidney failure
• Hypoparathyroidism 
• Vitamin D deficiency
• Pancreatitis
• Prostate cancer
• Malabsorption conditions
• Medications like heparin, osteoporosis drugs, and antiepileptics 

Magnesium

Hypermagnesemia

• Addison's disease (adrenal condition)
• End-stage kidney disease

Hypomagnesemia

• Alcoholism
• Malnutrition and malabsorption
• Chronic diarrhea
• Excessive sweating
• Heart failure
• Medications like diuretics and antibiotics

Phosphate

Hyperphosphatemia

• Low calcium levels
• Chronic kidney disease
• Severe asthma and breathing conditions
• Underactive parathyroid gland
• Extreme muscle injury
• Complications of cancer treatments
• Excessive use of laxatives containing phosphate

Hypophosphatemia

• Acute alcohol abuse
• Severe burns
• Starvation
• Vitamin D deficiency
• Overactive parathyroid gland
• Medications like intravenous iron treatment, niacin, and antacids 

Bicarbonate

Acidosis (blood is too acidic; low blood pH)

• Hypoventilation
• Chest deformities and injuries
• Chronic lung diseases
• Neuromuscular disorders like muscular dystrophy
• Uncontrolled diabetes
• Severe diarrhea
• Kidney diseases
• Aspirin, ethylene glycol, or methanol poisoning
• Severe dehydration
• Vigorous exercise for an extended amount of time
• Carbon monoxide poisoning

Alkalosis

• Hyperventilation
• High fevers
• Oxygen deprivation
• High altitude exercise
• Liver and adrenal diseases
• Lung diseases
• High antacid (TUMS) consumption
• Ingestion of baking soda
• Laxative use
• Alcohol abuse

In Summary

Electrolytes are essential minerals like sodium, potassium, calcium, and magnesium that carry electrical charges in the form of cations or anions. They literally generate electricity in the presence of water to facilitate numerous metabolic reactions like muscle contraction, nerve impulse, fluid and pH balance, and tissue growth and maintenance. 

Maintaining a healthy electrolyte balance important for overall health - and especially heart health and athletic performance. 

High-water foods - like fruits and veggies - are some of the best sources. Nuts, seeds, whole grains, and some seafood are good sources of electrolytes. Eating a wide variety of plant foods and potentially supplementing with an electrolyte drink is a wise way to avoid imbalances. 

References:

Electrolytes: Types, Purpose and Normal Levels. Cleveland Clinic. Reviewed September 24, 2021. https://my.clevelandclinic.org/health/diagnostics/21790-electrolytes.

Holland K. What You Need to Know about Electrolyte Disorders. Healthline. Updated April 29, 2019. https://www.healthline.com/health/electrolyte-disorders#diagnosis.

Kaminski J. NASM. https://blog.nasm.org/foods-to-replenish-electrolytes. 

West H. Electrolytes: Definition, Functions, Imbalance, and Sources. Healthline. Updated October 24, 2018. https://www.healthline.com/nutrition/electrolytes#functions.