Electrolitos: qué son y por qué es malo que se desequilibren

Our body starts the sweat mechanism. That water that we lose when we sweat also carries some minerals, so when it comes to rehydrating after intense exercise, drinking water is not enough. It is necessary also replenish mineral salts that we have lost to rebalance the levels of electrolytes, essential substances for the electrical connection between our neurons and muscles.

What are electrolytes in the human body?

Marhuenda Hernández, professor at the Faculty of Pharmacy and Nutrition of the UCAM and member of the Sports Nutrition Group of the Spanish Academy of Nutrition and Dietetics, explains that electrolytes are “substances that are found in the human body in a predominantly sales form. minerals, such as sodium, potassium, calcium and magnesium. They dissolve in the body’s water and separate into positive and negative ions. This causes them to have a charge, which is why their passage into a tissue causes a potential difference,” says the expert.

What are electrolytes used for?

Electrolytes play a very important regulatory role within the body. “They contribute to maintain the balance of fluids inside and outside the cellensuring that both hydration and blood volume are adequate,” says Marhuenda.

Furthermore, they are essential for muscle contractionseven for heart function, and plays an essential role in impulse transmission electrical through our nervous system.

What are the symptoms of an electrolyte imbalance?

When we sweat excessively, an electrolyte deficiency can appear. The symptoms are «fatigue, weakness, headache, confusion, muscle spasms, irregular heartbeat and, finally, seizures if not controlled,» says Marhuenda. «This results in a disruption of the electrical balance required in muscle contraction and nerve impulse transmissions.»

How to recover electrolytes?

To reverse this deficit, it is enough to consume foods and drinks that contain them. In fact, in cases of mild to moderate dehydration, water and a healthy diet rich in minerals are usually enough.

If there is a greater loss of electrolytes, “oral rehydration solutions are offered. In very serious circumstances, intravenous solutions can be administered,” says the academic.

What foods contain electrolytes?

Foods rich in electrolytes are many, very varied and can easily be found in the pantry at home.

• potassium: present in dried fruits in general, bananas, potatoes, nuts and a wide variety of fruits and vegetables.
• sodium: table salt and processed foods (sausages, preserves, bagged snacks, etc.) and salted foods. It is important to remember that salt should be taken in moderation in the diet.
• calcium: especially in dairy products.
• magnesium: It is easy to find in foods such as nuts, oilseeds and legumes.

Sports drinks and other electrolyte supplements.

Sports drinks, gels and some powder supplements are specifically formulated with electrolytes to replenish the amount lost in the body during intense exercise. They are easy to acquire and are effective.

“Mainly, they include sodium and potassium. However, a person should use these drinks based on their individual needs and their activity level, since most recreational athletes do not need to drink them, except in very aggressive weather conditions,” recommends Marhuenda.

Drinks with electrolytes, only for after sports?

Although most athletes prefer to drink these types of drinks with electrolytes for post-exercise recovery, these sports drinks have uses beyond recovery after intense sports practice. “They can be helpful in a situation in which there is a significant loss of electrolytes, such as in an illness with vomiting or diarrhea, or in very hot climates with abundant sweat loss.” In any case, the dietician-nutritionist does not recommend its general consumption for the sedentary population or occasional athletes.

When and how to take them?

Depending on the needs and situation of the person who is going to consume these drinks, it is possible to introduce them during the activity to maintain correct hydration. “It would be the most normal, since that is when we will need the electrolytes that we lose through sweating.”

They can also be consumed “after activity, to assist in restoring losses that occur with increased duration or intensity resulting from exercise. It is essential to combine them with an adequate water intake.” The latter applies to cases in which the athlete buys the powder product and rehydrates it himself. “It is very important to follow the instructions on the product label,” says the expert.

Should we set limits on the intake of these drinks?

This question does not have a simple answer since, as Marhuenda Hernández states, “it depends on the person, the level of activity and the environmental condition, in addition to the formulation of the product in question. An excessive amount of electrolytes—especially sodium and potassium—can be harmful and cause, among other conditions, hypernatremia or hyperkalemia, causing heart problems and changes in blood pressure, respectively.”

For this reason “it is key to take the recommended doses of supplements. The athlete should adjust his intake according to exercise and the recommendations of a sports dietitian-nutritionist,” he concludes.

Post Expert: Javier Marhuenda

Javier Marhuenda. Dietitian-nutritionist, with an outstanding doctorate cum laude and an Official Master’s Degree in Clinical Nutrition (2011), Teacher Training (2012) and Nutrition and Food Safety (2017). He is a full academician of the Spanish Academy of Human Nutrition and Dietetics and Member of the Sports Performance Specialization Group. He is director of the Master of Sports Nutrition in Special Populations (CEU-Cardenal Herrera), professor and researcher at UCAM-University and Member of the research groups «Sport Physiology» and «Bioavailability of Bioactive Compounds». INSTAGRAM: @jmarhuenda_phd Head of the nutrition area at UCAM CF and former Albacete Balompié SAD

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