Electrolytes: When should you take them?
ca. 17 Minuten
Electrolyte drinks and powders are no longer just for competitive athletes. But does everyone really need extra electrolytes—or is it often just clever marketing?
You should make a point of getting electrolytes mainly when you lose a lot or take in too little: during intense or prolonged exercise, when sweating heavily in the heat, when illness causes diarrhea or vomiting, and when following a very low-carb diet. For most people who eat a balanced diet, however, regular food provides enough—so additional electrolytes aren’t necessary and can even be harmful in excess.
This article is best read from the basics through to specific situations: First, you’ll learn what electrolytes are and what your body needs them for. Then, you’ll look at each situation to find out when additional intake may be beneficial—and when it isn’t.
What to expect in this article
When are extra electrolytes useful?
How can you tell if you have an electrolyte deficiency?
How much do you need - and can you have too much?
Electrolytes from food or supplements?
When you don’t need extra electrolytes
Know your mineral status
Putting things in perspective: What a test can and can’t do
Conclusion
Frequently asked questions (FAQ)
Sources
Electrolytes is a collective term for several minerals that carry an electrical charge in the body. This overview shows the most important ones, their roles, and how you can get them through your diet:
| Electrolyte | Role in the body | Good food sources |
|---|---|---|
| Sodium | Fluid balance, nerves, muscles | Table salt, bread, processed foods |
| Potassium | Muscle and heart function, blood pressure | Vegetables, fruit (e.g., bananas), potatoes, legumes |
| Magnesium | Muscles, nerves, energy metabolism | Nuts, whole grains, green vegetables, legumes |
| Calcium | Bones, muscle contraction, nerves | Dairy products, green vegetables, calcium-rich water |
| Chloride | Fluid balance, stomach acid | Table salt (sodium chloride) |
Here’s an overview of the four most common situations in which additional intake may be beneficial:
Long & intense workouts
After about an hour of strenuous activity with heavy sweating, you lose significant amounts of sodium.
Heavy sweating
In hot weather and during physical work, you mainly lose sodium through sweat.
Diarrhea & vomiting
This is when you lose a lot of fluid and electrolytes—rehydration solutions can help.
Keto & fasting
When you eat very few carbohydrates, your body excretes more sodium.
What are electrolytes, and what does your body need them for?
Electrolytes are minerals that carry an electrical charge when dissolved. The most important include sodium, potassium, magnesium, calcium, and chloride. They regulate key processes in your body—from fluid balance and nerve signaling to muscle contractions, including your heartbeat.
Put simply, electrolytes ensure that the right electrical charge is maintained in your cells and that signals can be transmitted. When their balance is disrupted, you can quickly notice it—for example, through muscle cramps, fatigue, or circulation problems.
Key takeaway: Electrolytes aren’t a niche concern for athletes; they’re essential for every cell. What matters isn’t “as much as possible,” but a balanced equilibrium—which the body usually regulates on its own.
Sodium and chloride—the salt component
Sodium and chloride together make up table salt (sodium chloride) and primarily regulate fluid balance and blood pressure. Sodium is the electrolyte you lose most through sweating—so sodium is at the heart of almost every discussion about sports electrolytes.
Potassium—the counterbalance
Potassium works together with sodium and is especially important for muscle and heart function and healthy blood pressure. It’s abundant in vegetables, fruit, potatoes, and legumes—a plant-focused diet usually provides enough.
Magnesium and calcium—muscles and bones
Magnesium is involved in hundreds of metabolic processes and plays a role in muscle relaxation and energy production. Calcium is especially important for bones and muscle contractions. You can get plenty of both from nuts, whole grains, green vegetables, and dairy products.
How does your body maintain balance?
Your body regulates its electrolyte balance very precisely—mainly through the kidneys and various hormones. If you take in too much of an electrolyte, your body generally excretes the excess; if levels are low, it holds on to more. That’s why healthy people who eat a balanced diet rarely become imbalanced. It only becomes a concern when losses are very high or regulation is disrupted, for example by illness or medication.
When are extra electrolytes useful?
Extra electrolytes are useful when your body loses more or takes in less than usual. In these four situations, it’s worth paying attention to your intake.
During intense or prolonged exercise
When you exercise, you lose fluids and sodium through sweat. For short, easy sessions, water is all you need. Replacing electrolytes only becomes relevant during longer or more intense exercise.
During intense exercise lasting about an hour—especially in hot weather—taking in sodium as well as fluids is recommended to replace losses through sweat (ACSM, 2007; DGE Sports Nutrition Working Group, 2020).
In practice, this means that for a workout under an hour, you generally don’t need electrolytes, just water. But if you run or cycle for a long time, or sweat a lot in the heat, an electrolyte drink can help—for example, a juice spritzer with a pinch of salt or a sports drink made for that purpose.
How much you lose varies from person to person: Some people sweat more or have “saltier” sweat than others, which you can tell from white salt marks on your skin or clothing after a workout. If that sounds like you and you regularly do long workouts, you should be a little more mindful about replacing sodium than someone who sweats only a little.
In hot weather and when sweating heavily
Even without exercising, you can sweat a lot and lose sodium in extreme heat or while doing physical work outdoors. Anyone who sweats heavily on hot days should drink enough and make sure they get enough salt—with very heavy sweating throughout the day, an electrolyte drink may be helpful.
Muscle cramps, dizziness, or headaches in hot weather are warning signs of an imbalance. They signal that you should slow down, get into the shade, and replenish fluids and electrolytes.
When ill with diarrhea or vomiting
With gastrointestinal infections involving diarrhea or vomiting, the body loses a lot of fluid and electrolytes in a short time. This is when targeted replacement is especially important—particularly for children and older people.
For diarrhea and vomiting, oral rehydration solutions made from water, salt, and sugar are the treatment of choice for replacing fluids and electrolytes (World Health Organization, WHO).
These solutions are available ready-made at pharmacies. However, persistent or severe diarrhea, a high fever, blood in the stool, or signs of dehydration require medical attention—especially for infants, young children, and older or frail people.
With a low-carbohydrate diet or fasting
With a very low-carbohydrate diet such as keto, or while fasting, insulin levels drop, causing the kidneys to excrete more sodium. This explains why some people experience fatigue, headaches, and circulation problems during the first few days of switching to a low-carb diet—often called “keto flu.”
In these cases, consciously adding sodium (a little more salt), potassium, and magnesium may ease symptoms. The important thing is not to overdo it just in case, but to adjust intake to your actual needs and tolerance.
With certain medications and life circumstances
Some medications - such as diuretics or laxatives - affect electrolyte balance. Pregnancy, breastfeeding, and certain medical conditions can also change your needs. In these cases, don't start taking extra electrolytes on your own; consult a doctor, as too much or too little can have serious consequences.
How can you tell if you have an electrolyte deficiency?
An electrolyte imbalance often causes nonspecific symptoms, which can also have many other causes. Typical signs include muscle cramps and twitching, fatigue and weakness, headaches, dizziness, and a racing or irregular heartbeat.
Precisely because these symptoms are so general, a deficiency cannot be identified based on symptoms alone. For example, muscle cramps during exercise are often automatically blamed on magnesium deficiency, even though they can have many causes - from overexertion to dehydration.
Key point: Symptoms such as muscle cramps or fatigue are clues, but not proof of an electrolyte deficiency. A blood test, interpreted in a medical context, is the only way to be sure.
Take persistent or severe symptoms seriously: A significant electrolyte imbalance - especially involving sodium or potassium - can affect your heart rhythm and should be assessed by a doctor. Supplementing on your own without knowing the cause is not a good idea.
It helps to consider the circumstances: if symptoms occur after heavy sweating, a gastrointestinal illness, or a change in diet, an electrolyte-related cause is more likely. If there is no such trigger and the symptoms persist, other causes should also be checked by a doctor - from thyroid problems to iron levels.
How much do you need - and can you have too much?
A balanced diet usually provides enough electrolytes; the German Nutrition Society (DGE) provides recommended values. In Germany, the reality is actually the opposite when it comes to sodium: most people consume too much salt, rather than too little, through processed foods.
So remember: more is not better. Consistently high salt intake is associated with high blood pressure. And targeted replenishment during exercise also has a dangerous downside that is often underestimated.
Drinking too much while consuming too little sodium can cause dangerous dilutional hyponatremia (low sodium levels) during prolonged endurance exercise (Hew-Butler et al., 2017).
That means someone who drinks liters of plain water during a marathon without replacing sodium is more likely to run into a problem than someone who drinks moderately and includes electrolytes. So the right amount depends on actual losses - not on the principle of “as much as possible.” People with kidney or heart disease need to be especially careful; in these cases, electrolyte intake should be managed by a doctor.
A simple rule of thumb for everyday life is to listen to your thirst and your body’s signals instead of rigidly aiming for a fixed number of liters. Thirst is a reliable regulator in healthy people. Only during very prolonged exertion, in hot weather, or when you’re ill is it worth paying closer attention to your fluid intake and keeping an eye on electrolytes too.
Electrolytes from food or supplements?
For everyday needs, the best way to get electrolytes is through your regular diet. A varied, wholesome diet with vegetables, fruit, nuts, whole grains, legumes, and - in moderation - salt generally provides everything your body needs.
Specifically, that means a banana or potatoes for potassium, nuts and whole grains for magnesium, dairy products or green vegetables for calcium, and using a normal, moderate amount of salt for sodium. That provides most people with everything they need.
Supplements or electrolyte drinks are most useful in the exceptional situations mentioned above: prolonged exercise, heavy sweating, illness involving fluid loss, or a very low-carb diet. They’re usually unnecessary as a long-term solution for healthy, normally active people - and you should only take individual high-dose minerals after a confirmed deficiency and ideally under medical supervision.
It’s also worth checking the ingredient list: many electrolyte products contain plenty of sugar, flavorings, or sweeteners. During prolonged exercise, some sugar can be useful because it helps the body absorb sodium and water - but it’s usually unnecessary in everyday life. If you mix your own, you have full control: water, a pinch of salt, and a little juice are enough for most situations.
When you don’t need extra electrolytes
Just as important as “when” is “when not.” With normal physical activity, moderate temperatures, and a balanced diet, you don’t need extra electrolytes. Water is perfectly adequate for a short workout, a walk, or a normal day at the office.
Electrolyte drinks often contain added sugar and calories that you don’t need in these situations. Consuming them as everyday drinks offers no benefit to healthy people and can even be counterproductive when it comes to sodium. In short: electrolytes are a tool for special situations, not a daily necessity.
The same is true for most recreational athletes: if you work out for an hour three times a week and eat a balanced diet, you don’t need special electrolyte products. They’re mainly useful for serious endurance sports, physically demanding work in hot weather, or the exceptional situations mentioned above—not for the average training routine.
Key takeaway: For healthy people with a balanced diet and normal activity levels, additional electrolytes are generally unnecessary—water and a varied diet are all you need.
Know your mineral status
If you have recurring symptoms such as fatigue or muscle cramps and want to know whether your mineral levels are in the healthy range, a checkup can help. A blood test shows where your levels actually stand—instead of supplementing on a hunch.
The Nutrient | VitalCheck Complete from mybody® (MYBODY Lab GmbH) measures 15 values from an at-home capillary blood sample—including the electrolytes sodium, calcium, and magnesium, as well as vitamin D, B12, iron (ferritin), zinc, and selenium. The sample is analyzed in an ISO-certified, GDPR-compliant laboratory. To be clear: potassium is not included in this test, and a home test does not replace a medical diagnosis.
Nutrient | VitalCheck Complete
Comprehensive at-home blood test—including the minerals sodium, calcium, and magnesium, as well as important vitamins and trace elements. For a well-founded overview of your nutrient and mineral status.
Price: €169.00 (instead of €199.00) · Sample type: Capillary blood (at home) · Processing time: approx. 10–15 business days · Laboratory: ISO-certified, GDPR-compliant
View the nutrient checkInformation on price, sample type, processing time, and markers comes from the mybody® product page (as of July 2026) and may change. A home test does not replace a medical diagnosis.
Putting things in perspective: What a test can and can’t do
A blood test can show individual mineral levels and give you an indication of whether they are within the normal range. It is therefore a helpful tool to avoid supplementing blindly—but it does not replace a medical diagnosis.
Another important point: The electrolyte level in your blood is a snapshot and is tightly regulated by your body. A routine test may not necessarily capture an acute imbalance, for example after heavy sweating or during an illness. Abnormal results or persistent symptoms should therefore always be assessed by a doctor.
Use a test as a supplement, not a substitute: as a way to assess your current status and prepare for a conversation with your doctor, who will decide on diagnosis and treatment.
Conclusion
You should take electrolytes specifically when your body loses a lot or takes in too little: during long or intense exercise, when sweating heavily in the heat, when sick with diarrhea or vomiting, and when following a very low-carb diet. In these situations, an electrolyte drink or rehydration solution can help restore your balance.
For everyday life with a balanced diet, you usually don’t need extra electrolytes - in fact, most people get too much sodium rather than too little. Pay attention to your body’s signals, meet your needs primarily through your diet, and have any persistent symptoms or unusual findings checked by a doctor. A mineral test can give you an initial indication.
Frequently asked questions (FAQ)
Instead of guessing: know your levels
Sodium, calcium, magnesium, and other nutrients as a baseline: The nutrient | VitalCheck Complete measures these values from a blood sample taken at home – ISO-certified and GDPR-compliant.
Explore nutrient testsYou might also be interested in
→ At-home vitamin and mineral test
How to check and assess your vitamin and mineral intake.
→ Test for nutrient deficiencies: recognize symptoms and address them effectively
Which signs indicate a deficiency, and what really helps.
Sources
- American College of Sports Medicine (ACSM), Sawka, M. N. et al. (2007): “Exercise and Fluid Replacement" (Position Stand, Medicine & Science in Sports & Exercise) – fluid and sodium replacement during exercise. pubmed.ncbi.nlm.nih.gov
- Sports Nutrition Working Group of the German Nutrition Society (DGE) (2020): “Fluid Replacement in Sports" – recommendations on fluids and electrolytes. germanjournalsportsmedicine.com
- World Health Organization (WHO): “Oral rehydration salts" – composition and use of oral rehydration solutions. who.int
- Hew-Butler, T. et al. (2017): “Exercise-Associated Hyponatremia: 2017 Update" (Frontiers in Medicine) – risk of dilutional hyponatremia. frontiersin.org
- German Nutrition Society (DGE) – reference values and recommendations for minerals. dge.de
Recommendations on sports and sweat losses are based on [1][2], those on oral rehydration during illness on [3], the warning about dilutional hyponatremia on [4]; general reference values are based on [5]. Product-specific information from mybody® (price, sample type, processing time, markers) comes from the respective product page on mybody-x.com and may change.
mybody® Editorial & Expert Team
This article was created by the mybody® editorial and expert team, which brings together expertise in nutritional science, blood test interpretation, laboratory diagnostics, and sports and metabolic science. Learn more about our team on our editorial and authors page.
Published on July 24, 2026 · Last updated on July 24, 2026
Medical disclaimer: This article is for general information only and is not a substitute for medical advice, diagnosis, or treatment. If you have persistent symptoms, pre-existing conditions (e.g., affecting your heart or kidneys), or are taking medication, please consult a doctor.
