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When you say potassium, most people immediately think of bananas. They are perhaps the most well-known source of this essential mineral, and for good reason! Bananas are a popular snack, especially among endurance athletes, who rely on them during intense training sessions or competitions for a quick boost of energy and potassium. This mineral plays a key role in proper muscle function and maintaining optimal hydration. However, its impact on sports performance and health goes far beyond that. In today’s article, we’ll explore everything potassium influences, from its basic functions to the symptoms of deficiency and excess, as well as the best food sources and supplementation options.
In the article, you’ll learn about the effects of potassium on:
What Is Potassium?
Potassium (Latin: kalium) is a mineral commonly found in the Earth’s crust, seawater, and living organisms. It is a soft, silvery metal that is highly reactive with both water and air. If you were to drop a piece of pure potassium into water, it would result in an immediate and explosive reaction. Due to this high reactivity, potassium does not exist in its pure form in nature but only in compounds, such as potassium salts.
In the human body, potassium primarily exists in the form of a cation (a positively charged ion), which is present in every tissue. It plays a crucial role in transmitting nerve impulses and, as an electrolyte, is involved in regulating fluid balance both inside and outside of cells.
Potassium is an essential nutrient that our body cannot produce on its own. Additionally, we are unable to store reserves for later use. This is why it’s important to maintain a well-balanced diet with plenty of potassium-rich foods and, if necessary, consider dietary supplements to ensure adequate intake. [1–2]
What Is the Function of Potassium in the Body?
Approximately 90% of the absorbed potassium is used by the body to maintain its optimal levels, both inside and outside of cells. This balance is particularly important for the proper functioning of three key bodily processes. [1]
1. It supports the normal functioning of the nervous system
Potassium is key for the transmission of nerve impulses between cells. It functions as an electrolyte, regulating the electrical charge across cell membranes. It moves between the internal and external environments of the cell, enabling proper signal transmission. This process is essential for all nervous system functions, from reflexes to conscious movements. [3]
2. It helps maintain normal blood pressure
Both sodium and potassium influence blood pressure regulation. Sodium retains water in the body, ultimately increasing blood pressure. Potassium, on the other hand, helps the body excrete excess sodium, which supports the removal of surplus water, leading to a reduction in blood pressure. This process is essential for the proper functioning of the heart and blood vessels. [5]
3. It contributes to proper muscle function
This mineral also plays a role in muscle contraction (the tightening and relaxing of muscles), which occurs in response to nerve impulses. During each muscle contraction, there is an exchange of potassium and sodium between the internal and external environments of the muscle cell. This sodium-potassium pump helps maintain the correct charge inside and outside the cell, allowing it to respond properly to signals from the nervous system. Without this mechanism, our muscles simply wouldn’t function effectively. [4]
What Are the Effects of Potassium on Health and Sports Performance?
Adequate potassium intake is crucial for maintaining overall health and sports performance. Due to modern dietary habits, which often lack fresh foods and are high in ultra-processed items, there is a risk of potassium deficiency. This deficiency can negatively impact both health and physical performance. Health authorities, such as the WHO and the European Society of Cardiology, frequently highlight the importance of sufficient potassium intake. This is why the DASH diet exists, which is rich in fresh vegetables, fruits, legumes, whole grains, and other potassium-rich foods. It is recommended for the prevention of high blood pressure and other cardiovascular diseases. [6–7]
What areas of our everyday lives does it impact the most?
1. Supports heart function
Potassium influences heart function on multiple levels. Firstly, as one of the main electrolytes, it plays a crucial role in transmitting electrical signals between heart cells. This is essential for maintaining a regular heart rhythm, allowing the heart muscle to contract and relax effectively. As a result, blood is pumped efficiently throughout the body. [6]
This mineral also impacts heart function through its effect on blood pressure. As mentioned earlier, it helps excrete excess sodium, thereby regulating the volume of circulating blood. This action reduces the risk of developing high blood pressure (hypertension), which places a significant strain on the heart.
The positive effect of potassium on heart function and blood pressure is supported by numerous studies. For example, they show that increased potassium intake leads to a reduction in blood pressure among individuals with hypertension. Additionally, this reduction also lowers the risk of stroke by as much as 24%. The findings suggest that increasing potassium intake has beneficial effects on heart and vascular health. However, this applies only to individuals with healthy kidneys, which can adequately excrete excess potassium and prevent its accumulation in the body. [8, 11]
What dietary changes can help lower blood pressure?
For those looking to adjust their diet to prevent hypertension, the DASH diet (Dietary Approaches to Stop Hypertension) is recommended. This diet is based on a balanced and varied intake of nutrient-rich foods that help regulate blood pressure, particularly potassium, calcium, and magnesium. The core principle is to reduce sodium (salt) intake while increasing the consumption of healthy foods such as whole grains, legumes, fruits, vegetables, lean meats, and low-fat dairy products. Conversely, it limits fatty meats, sugary beverages, sweets, and other highly processed foods. [27]
2. Supports proper kidney function
Optimal potassium intake is also linked to kidney function, primarily because it helps regulate fluid volume in the body. It supports the excretion of excess sodium, preventing water retention in the body and thereby easing the burden on the kidneys. Studies suggest that adequate potassium intake is also associated with a lower risk of developing kidney stones. This is largely due to potassium’s ability, particularly in the form of potassium citrate, to bind with calcium, preventing the accumulation and formation of calcium stones. Additionally, potassium aids the kidneys in maintaining acid-base balance by participating in the excretion of excess acids. Thus, optimal potassium levels in the body rank among the factors that help keep the kidneys healthy. [1, 9]
3. Supports bone health
Adequate potassium intake is also important for bone health. Studies indicate that this is due to its influence on maintaining acid-base balance (pH) and reducing calcium leaching from the bones. Experts explain that potassium helps decrease acidity in the body, keeping pH at optimal levels. Without potassium’s role in this process, calcium would have to combat the acidic environment, leading to unwanted calcium depletion from the bones. This could ultimately result in conditions such as osteoporosis, also known as bone thinning. [16]
Conclusions from several studies also indicate that adequate potassium intake is associated with improved calcium absorption from the diet and promotion of bone mineralization. Some experts also mention a potential positive effect of potassium on the conversion of vitamin D into its active form, which is no less important for bone health. [17]
4. Contributes to the maintenance of healthy blood sugar levels
Potassium is also involved in glucose metabolism. It affects the release of insulin, the hormone that regulates blood sugar levels and keeps them within a healthy range. Potassium plays a key role in the process of insulin secretion from the beta cells of the pancreas. However, when potassium levels are low, this can negatively impact insulin release, leading to elevated blood sugar levels (hyperglycaemia) and an increased risk of insulin sensitivity issues (insulin resistance), potentially progressing to type 2 diabetes mellitus. [1]
Several studies have found a connection between low potassium levels and hyperglycaemia, insulin resistance, and type 2 diabetes mellitus. This effect has been particularly observed in groups of people with lower dietary potassium intake. [18–19]
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5. Helps maintain optimal hydration
Along with sodium, potassium is responsible for maintaining proper hydration in the body. Sodium primarily oversees the optimal fluid balance in extracellular fluid (outside the cells), while potassium regulates hydration within the cells. Together, these minerals collaborate to ensure balanced water distribution throughout the body. This is especially important during significant water loss, such as when sweating heavily during exercise or when ill. Potassium and sodium help prevent dehydration, which could negatively impact not only sports performance but also overall health. [10]
Due to these properties, potassium is also added to sports (electrolyte) drinks, which are particularly beneficial during long or high-intensity workouts when sweating is significant and the risk of dehydration is high. In such cases, simply drinking water is often not enough. Sweat leads to the loss of electrolytes, which also need to be replenished for optimal hydration.
If you want to learn more about sports drinks and their use during workouts, check out the article: Sports Drinks: When to Drink an Ion Supply Drink or Water?
6. Contributes to proper muscle function during sports performance
Potassium is vital for muscle movement, playing a key role in transmitting signals from the nervous system to the muscles. Without it, we wouldn’t be able to spring into action for a squat or a jump at a moment’s notice. Potassium enables us to react swiftly to unexpected stimuli, like catching a ball thrown our way. This quick reflex is what we call reaction speed.
During athletic performance, potassium shifts from the cells into the intercellular space. This transfer is essential for neuromuscular transmission and, consequently, muscle contraction. However, this rapid exit of potassium from the cells can lead to a deficiency. Combined with losses through sweating, this further exacerbates the potassium deficit. As a result, we may notice diminished muscle function and quicker onset of fatigue during training. A serious potassium deficiency can manifest as muscle cramps and, in extreme cases, even heart rhythm disturbances (arrhythmia). [13–15]
Endurance athletes are particularly at risk of reduced performance due to low potassium levels. They are often advised to replenish potassium and other electrolytes during their activities. That’s why they typically bring a banana for longer workouts or sip on an electrolyte drink, and some even take electrolyte tablets. It’s also crucial to replenish potassium after training, which can be effectively achieved with a nutritious meal.
Magnesium also supports proper muscle function. If you’d like to learn more about it, check out the article: Cramps, Fatigue, Irritability or Sleep. What Else Does Magnesium Affect?
What Can Happen in the Case of Potassium Deficiency?
A potassium deficiency (hypokalaemia) is a serious condition that can affect the functioning of the entire body. Despite potassium being present in many common foods, it’s often lacking in people’s diets, especially among those who prefer ultra-processed foods over fresh ones. This is commonly referred to as the Western diet. A low intake of this essential mineral is therefore the primary cause of potassium deficiency. [15, 20]
Symptoms of potassium deficiency
- fatigue
- muscle weakness and cramps
- digestive issues (constipation)
- tingling, reduced sensitivity in the limbs
- frequent urination (polyuria)
- high blood pressure
- heart rhythm disorders (arrhythmia)
Causes of potassium deficiency
Hypokalaemia doesn’t only arise from low intake; sometimes the cause lies elsewhere and can indicate a more significant issue. [15, 20]
- increased sweating
- high sodium intake
- low magnesium levels
- digestive issues (vomiting, diarrhoea)
- eating disorders (bulimia)
- use of medications (diuretics)
- kidney diseases (hyperaldosteronism)
- genetic conditions (Bartter syndrome)
At-risk groups for potassium deficiency
Who Is Most Often Affected by Hypokalaemia? [1]
1. People with chronic kidney disease
People with kidney disease may struggle to maintain electrolyte balance, including potassium. The kidneys’ inability to effectively regulate potassium levels can result in a deficiency.
2. People with long-term digestive issues
Prolonged digestive issues, such as diarrhoea or vomiting, can result in increased potassium loss. This includes individuals with inflammatory bowel diseases like Crohn’s disease or ulcerative colitis. In their case, impaired absorption of potassium from food can lead to its low levels in the blood.
3. People who use diuretics or laxatives
Some medications that promote urination (diuretics) can lead to increased potassium excretion by the kidneys. In the case of laxatives, higher potassium loss occurs primarily through the digestive tract (in faeces). Those at risk are especially individuals who use these medications over an extended period of time.
4. Athletes and individuals who sweat profusely
When we sweat, we lose electrolytes, including potassium. This is particularly common among endurance athletes, those working in hot environments, and anyone who tends to sweat a lot during everyday activities.
5. Individuals with an unbalanced diet or eating disorders
People at risk of insufficient potassium intake often include those with restricted diets, who skip entire food groups (like fruits, vegetables, and legumes), or who generally lack sources of this essential mineral. Extreme cases arise with eating disorders such as anorexia or bulimia, where an overall extremely low food intake makes potassium one of the nutrients that can quickly become deficient. A rare condition known as pica can also be the culprit, where individuals consume inedible substances or objects (like cotton or dirt), which can bind potassium in the intestines and hinder its absorption into the bloodstream.
What problems can arise from elevated potassium levels?
If you have healthy kidneys, you don’t need to worry about potassium overdose. Experts agree that this is a very rare occurrence, so there’s no need to set an upper intake limit for potassium. Your kidneys will take care of excreting excess potassium through urine. However, moderation is key, so it’s important to stick to the recommended intake levels for potassium.
People with chronic kidney disease or those taking certain medications that affect potassium metabolism (like ACE inhibitors or potassium-sparing diuretics) can’t rely on their bodies to naturally get rid of excess potassium. For them, even a slightly lower intake than the recommended daily amount can lead to high blood potassium levels (hyperkalaemia). This also applies to individuals with type 1 diabetes, congestive heart failure, liver disease, or adrenal insufficiency, who are particularly at risk. [1, 21]
Symptoms of elevated blood potassium levels
- muscle weakness
- paralysis
- heart palpitations
- paresthesia (burning sensation in the limbs)
- heart arrhythmia
It’s clear from these symptoms that hyperkalaemia is a serious, sometimes even life-threatening condition. Therefore, individuals at risk of potassium build-up in their bodies are advised to follow a low-potassium diet. The goal isn’t to eliminate potassium entirely—since it plays an essential role in the body—but to be aware of which foods contain it and to limit those. A nutritional therapist can provide the best guidance for creating a meal plan when blood potassium levels are elevated.
How Can I Check My Potassium Levels in the Body?
If you suspect a potassium deficiency, the best way to check your current levels is to visit a doctor. They will first discuss your symptoms with you and assess whether blood tests are necessary. Your blood will then be sent for analysis, and the results will be shared with you at your next appointment.
Reference values for potassium
These values for adults can vary slightly between hospitals, clinics, and other healthcare facilities, but typically these differences are minor. [22]
- Normal potassium level in the blood: 3.5–5.0 mmol/L
- Low potassium level in the blood (hypokalaemia): < 3.5 mmol/L
- High potassium level in the blood (hyperkalaemia): > 5.0 mmol/L
How to Replenish Potassium?
If you rank among those at risk of hypokalaemia or have already been diagnosed with low potassium levels based on tests, you may be wondering how to increase your potassium intake. Foods rich in this nutrient, as well as dietary supplements, can help with that.
1. Potassium in foods
If you want to focus on adequate potassium intake, you should definitely include these foods in your diet. [23]
| beans | 1540 mg |
| freeze-dried apricots | 1160 mg |
| lentils | 677 mg |
| spinach | 558 mg |
| avocado | 507 mg |
| potatoes (with skin) | 413 mg |
| beetroot | 342 mg |
| banana | 326 mg |
| white yoghurt | 210 mg |
| orange | 166 mg |
How do cooking and other processing methods affect potassium levels?
Cooking and other food preparation methods can significantly affect potassium levels in foods. This is particularly relevant for individuals with hyperkalaemia, who often aim to reduce their intake of this micronutrient. [24]
- Boiling in water: When cooking vegetables or potatoes, potassium is released into the water. To minimize its loss, it’s advisable to use as little water as possible. Conversely, individuals with hyperkalaemia may use more water and then drain it, not reusing it for further cooking.
- Canned foods: Processing and preservation can lower the content of potassium. Fresh vegetables are therefore likely to have a higher potassium content than canned ones.
- Drying foods: During the drying process, potassium content becomes more concentrated as water is removed, while minerals remain. Therefore, 100 g of dried food, such as apricots, contains significantly more potassium than 100 g of fresh apricots.
- Baking and grilling: These methods are gentler on potassium content compared to boiling. They are a good option if you want to increase your intake of this micronutrient.
2. Potassium in dietary supplements
Potassium supplements are ideal for athletes who experience higher losses through sweat. They can also benefit individuals who don’t regularly consume foods rich in this nutrient. Dietary supplements with potassium come in various forms, such as potassium chloride, citrate, phosphate, aspartate, carbonate, or gluconate. This raises the question: “Which form of potassium is best?” Studies indicate that all forms have similar absorption rates, so you don’t need to worry too much about this. However, potassium citrate is one of the most popular forms. [1]
- You can take potassium in the form of a single-ingredient supplement.
- It is also found in electrolyte complexes, such as electrolyte tablets or effervescent tablets.
- It is part of sports drinks, electrolyte drinks, and intra-workout beverages that are suitable during exercise.
What Is the Recommended Daily Intake of Potassium?
- The European Food Safety Authority (EFSA) recommends a daily intake of 3,500 mg of potassium for adult men and women. This amount should be sufficient to maintain proper electrolyte balance and support cardiovascular health. [25]
- The D-A-CH societies recommend a daily intake of 4,000 mg for adult men and women. [26]
Final Summary: What Benefits Does Potassium Offer According to Studies?
- It supports normal functioning of the nervous system.
- It contributes to normal muscle function.
- It helps maintain normal blood pressure.
- It supports the function of the heart, blood vessels, and kidneys.
- It plays a role in the maintenance of healthy bones.
- It is involved in maintaining optimal blood sugar levels.
- It helps maintain optimal hydration.
- It aids in sports performance.
What Are the Main Takeaways?
In today’s article, you discovered that potassium is more than just a mineral essential for optimal muscle function and hydration; it plays a vital role in the proper functioning of the nervous system and the regulation of blood pressure. Adequate potassium intake also contributes to better sports performance, heart health, and kidney function. If you follow a balanced diet and regularly enjoy potassium-rich foods like bananas, potatoes, and spinach, you’re likely in the clear when it comes to deficiency. However, for active individuals, particularly endurance athletes and those with higher potassium needs, exploring the option of dietary supplements might be a smart move.
If you enjoyed the article and found the information useful, share it with your friends so they can also learn about the benefits of adequate potassium intake for their health and sports performance.
[1] Office of Dietary Supplements.Potassium. – https://ods.od.nih.gov/factsheets/Potassium-HealthProfessional/
[2] Livescience.Com. Facts About Potassium – https://www.livescience.com/29025-facts-about-potassium.html
[3] Kowey, P. R. The Role of Potassium. – https://doi.org/10.1007/978-1-4615-1061-1_18
[4] Clausen, T. Na+-K+ pump stimulation improves contractility in damaged muscle fibers. – https://doi.org/10.1196/annals.1363.021
[5] Www.Heart.Org. How Potassium Can Help Control High Blood Pressure. – https://www.heart.org/en/health-topics/high-blood-pressure/changes-you-can-make-to-manage-high-blood-pressure/how-potassium-can-help-control-high-blood-pressure
[6] ESC.Women urged to eat potassium-rich foods to improve their heart health. – https://www.escardio.org/The-ESC/Press-Office/Press-releases/Women-urged-to-eat-potassium-rich-foods-to-improve-their-heart-health
[7] WHO.Increasing potassium intake to reduce blood pressure and risk of cardiovascular diseases in adults. – https://www.who.int/tools/elena/interventions/potassium-cvd-adults
[8] Aburto, N. J., Hanson, S., Gutierrez, H., Hooper, L., Elliott, P., & Cappuccio, F. P. Effect of increased potassium intake on cardiovascular risk factors and disease: Systematic review and meta-analyses.– https://doi.org/10.1136/bmj.f1378
[9] Ferraro, P. M., Mandel, E. I., Curhan, G. C., Gambaro, G., & Taylor, E. N. Dietary Protein and Potassium, Diet–Dependent Net Acid Load, and Risk of Incident Kidney Stones. – https://doi.org/10.2215/CJN.01520216
[10] Open, Ernstmeyer, K., & Christman, E. Chapter 15 Fluids and Electrolytes. – https://www.ncbi.nlm.nih.gov/books/NBK591820/
[11] D’elia, L., Cappuccio, F., Masulli, M., Fata, E. L., Rendina, D., & Galletti, F.Effect of Potassium Supplementation on Endothelial Function: A Systematic Review and Meta-Analysis of Intervention Studies. – https://www.semanticscholar.org/paper/Effect-of-Potassium-Supplementation-on-Endothelial-D%E2%80%99elia-Cappuccio/3c66a60bfba6ad83df9fd6d8d667a1aee99d664c
[12] D’elia, L., Cappuccio, F., Masulli, M., Fata, E. L., Rendina, D., & Galletti, F. (2023). Effect of Potassium Supplementation on Endothelial Function: A Systematic Review and Meta-Analysis of Intervention Studies. Nutrients. https://www.semanticscholar.org/paper/Effect-of-Potassium-Supplementation-on-Endothelial-D%E2%80%99elia-Cappuccio/3c66a60bfba6ad83df9fd6d8d667a1aee99d664c
[13] Lindinger, M. I., & Cairns, S. P. Regulation of muscle potassium: Exercise performance, fatigue and health implications. – https://doi.org/10.1007/s00421-020-04546-8
[14] Castro, D., & Sharma, S. Hypokalemia. – http://www.ncbi.nlm.nih.gov/books/NBK482465/
[15] Healthdirect Australia. Potassium deficiency – https://www.healthdirect.gov.au/potassium-deficiency
[16] Singh, W., & Kushwaha, P. Potassium: A Frontier in Osteoporosis. – https://doi.org/10.1055/a-2254-8533
[17] Kong, S. H., Kim, J. H., Hong, A. R., Lee, J. H., Kim, S. W., & Shin, C. S. Dietary potassium intake is beneficial to bone health in a low calcium intake population: The Korean National Health and Nutrition Examination Survey (KNHANES) (2008-2011). – https://doi.org/10.1007/s00198-017-3908-4
[18] Chatterjee, R., Biggs, M. L., de Boer, I. H., Brancati, F. L., Svetkey, L. P., Barzilay, J., Djoussé, L., Ix, J. H., Kizer, J. R., Siscovick, D. S., Mozaffarian, D., Edelman, D., & Mukamal, K. J. Potassium and glucose measures in older adults: The Cardiovascular Health Study. – https://doi.org/10.1093/gerona/glu071
[19] Chatterjee, R., Colangelo, L. A., Yeh, H. C., Anderson, C. A., Daviglus, M. L., Liu, K., & Brancati, F. L. Potassium intake and risk of incident type 2 diabetes mellitus: The Coronary Artery Risk Development in Young Adults (CARDIA) Study. – https://doi.org/10.1007/s00125-012-2487-3
[20] MedlinePlus Medical Encyclopedia. Low blood potassium. – https://medlineplus.gov/ency/article/000479.htm
[21] Viera, A. J., & Wouk, N. Potassium Disorders: Hypokalemia and Hyperkalemia. – https://pubmed.ncbi.nlm.nih.gov/26371733/
[22] Collection and Panels.Potassium: Reference Range, Interpretation.– https://emedicine.medscape.com/article/2054364-overview?form=fpf
[23] FoodData Central. – https://fdc.nal.usda.gov/fdc-app.html
[24] Batista, R. A. B., Japur, C. C., Prestes, I. V., Fortunato Silva, J., Cavanha, M., & das Graças Pena, G. Potassium reduction in food by preparation technique for the dietetic management of patients with chronic kidney disease: A review. – https://doi.org/10.1111/jhn.12846
[25] EFSA. Dietary reference values for potassium.– https://www.efsa.europa.eu/en/efsajournal/pub/4592
[26] DGE. Kalium. – http://www.dge.de/wissenschaft/referenzwerte/kalium/
[27] NHLBI, NIH. DASH Eating Plan. – https://www.nhlbi.nih.gov/education/dash-eating-plan
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