Foodstruct Nutrition Search | Diet Analysis | Food Comparison | Glycemic Index Chart | Insulin Index Chart | Blog | Subscribe | Sign Up

Potassium — Food Sources, Daily Intake, Deficiency Symptoms

Article author photo Victoria Mazmanyan by Victoria Mazmanyan | Last updated on April 14, 2024
Medically reviewed by Arpi Gasparyan Article author photo Arpi Gasparyan

Potassium — Food Sources, Daily Intake, Deficiency Symptoms


Potassium is an essential mineral and electrolyte crucial in maintaining various physiological functions in the human body, such as nerve transmission, muscle contraction, and kidney function. 

This article delves into the significance of potassium in nutrition and its impact on health. It also discusses potassium’s absorption and metabolism, recommended intakes, deficiency, and more.


Absorption, Metabolism, and Regulation

Potassium is the most abundant positively charged ion in cellular fluid, and it is essential for maintaining normal cell function, particularly in muscle and nervous tissues.

In adults, the estimated total body potassium (K+) is around 46mmol/kg (about 1800mg/kg) for men and 39 mmol/kg (around 1500mg/kg) for women. Only a small portion of this, approximately 2%, is located in the extracellular fluid. Most potassium in the body is found within the intracellular space of skeletal muscle (1, 2, 3).

In healthy individuals, approximately 90% of dietary potassium is absorbed in the intestines, mainly through passive diffusion in the small intestine (3).

Normal serum potassium concentrations are kept in the range of 3.5 to 5.0 mmol/L. The body maintains this potassium balance by redistributing potassium inside and outside the cell, absorbing potassium in the gastrointestinal tract, and excreting it through the kidneys and intestines.

The redistribution of potassium is achieved through a pump found in almost all cell membranes called the sodium and potassium pump or Na+-K+-ATPase. This pump leads sodium ions into the cell and potassium ions out. This process leads to the formation of an electrical gradient used by neurons and muscles for nervous system function and muscle contraction (4). 

Around 90% of the potassium ingested is eliminated through the kidneys in urine, while approximately 10% is excreted through feces, with a minimal quantity lost through sweat (1).

The steroid hormone aldosterone, produced by the adrenal glands, is one of the main regulators of potassium in the body. It increases the elimination of potassium and reabsorption of sodium in the kidneys, thus increasing blood pressure.

Recommended Intakes 

Individual potassium needs may differ based on age, gender, physiological state, genetics, blood pressure status, and sodium intake. 

The table below presents the adequate daily potassium intake in mg, according to the Dietary Guidelines for Americans 2020-2025, based on age and gender (5).

 2 to 34 to 89 to 1314 to 1819 and above

The adequate intake of potassium for pregnant women above the age of 18 is 2900mg per day, while this value is 2800mg for lactating women (5).

Currently, blood pressure is the primary factor in determining potassium requirements. Studies indicate that individuals of African descent are more susceptible to hypertension and show greater responsiveness to potassium supplementation than individuals of European descent. Moreover, hypertensive individuals tend to benefit more from increased potassium intake than those with normal blood pressure, particularly if they consume a high-sodium diet (1).

Food Sources of Potassium

Typically, healthy adults get their dietary potassium primarily from vegetables, fruits, meats, and dairy products.

Some foods particularly rich in potassium include potatoes, tomatoes, beans, bananas, oranges, cantaloupes, black strap molasses, beef, turkey, and salmon (2).

The concentration of potassium tends to be greater in fruits and vegetables compared to cereals and meat.

The table below presents the potassium values of some foods rich in this mineral according to their average serving sizes.

Food NamePotassium ContentServing Size
Banana (raw)422mg118mg or 1 medium 
Potato (baked, with skin)792mg148g
Orange (raw)237mg131g or 1 fruit
Yogurt (Greek, plain, non-fat)240mg170g or 1 container
Turkey (roasted, whole)203mg85g or 3 ounces
Beef (roasted tenderloin)299mg85g or 3 ounces
Apricot (raw)402mg155g or 1 cup in halves
Spinach (boiled)135mg29g or 1 cup
Avocado (raw)728mg150g or 1 cup in cubes
Sweet Potato (baked, with skin)542mg114g or 1 medium

Adding salt to foods and draining the liquid leads to an exchange of sodium (Na+) for potassium (K+), reducing the potassium content of foods. Processed foods typically have higher sodium and lower potassium content than fresh foods (1, 2).

You can also find a list of foods high in potassium based on 100g servings. These include tarragon, raw soybeans, sun-dried tomatoes, spices, and beans.

Health Benefits and Functions of Potassium

Potassium's health benefits are vast and essential for overall well-being. This section delves into its multifaceted functions, from regulating blood pressure to supporting kidney and muscle function.

Blood Pressure and Cardiovascular Health

Numerous studies suggest that insufficient potassium intake raises the risk of hypertension, particularly when accompanied by high sodium consumption. Conversely, higher potassium intake levels have been linked to lowered blood pressure, partially attributed to enhanced widening of blood vessels and increased sodium excretion through urine, leading to reduced plasma volume (3).

The Dietary Approaches to Stop Hypertension or DASH diet focuses on vegetables, fruits, and whole grains, which are low in saturated fats and sodium and high in potassiumcalciummagnesium, protein, and fiber (6).

A systematic review of 171 studies concluded that increasing potassium consumption, lowering sodium intake, and integrating potassium-enriched salt substitutes into the diet notably reduce blood pressure levels, especially in individuals with hypertension (7).

Potassium also decreases the risk of stroke. A 12-year longitudinal study revealed that for every additional 10 mmol of potassium consumed daily, there was a significant 40% decrease in mortality linked to strokes (8).

Another study found that for every 1000mg of potassium consumed, the risk of cardiovascular disease decreased by 18% (9).

Kidney Stones

Inadequate potassium intake impedes calcium reabsorption in the kidneys, leading to higher levels of urinary calcium excretion, which may result in hypercalciuria (too much calcium in the urine) and the formation of kidney stones (3).

Among a group of 45,619 men aged between 40 and 75 years with no prior history of kidney stones, individuals with the highest potassium intakes (over 4mg/day) exhibited a 51% reduced risk of developing kidney stones over a 4-year follow-up period compared to those with the lowest intakes (less than 2,9mg/day) (10).

Another study found that individuals with a history of kidney stones who increased their potassium intake via potassium citrate supplements notably decreased the likelihood of recurring stones, provided they concurrently increased their fluid intake (11).

Bone Health

A hypothesis known as the "acid-base balance" or "acid-alkaline theory" suggests that a diet with a high acid load (increased meat consumption and inadequate intake of fruits and vegetables) might contribute to bone loss. This theory proposes that the components of animal proteins and grains rich in phosphorus and sulfates generate acidity within the body. This may lead to calcium loss from the bones, which neutralizes the acid and increases acid and calcium excretion through the kidneys (9).

Potassium-rich foods have the potential to provide an "alkalinizing" effect because they contain compounds that can be metabolized to bicarbonate. Bicarbonate helps neutralize acids in the body, potentially protecting bone health. Observational studies have indicated that a diet high in potassium from fruits and vegetables is linked with increased bone density (9).

In a clinical trial involving 201 healthy adults aged 65 or older, participants received daily potassium citrate supplementation, providing over 2,3mg of potassium for 2 years. The results showed that potassium supplementation led to a significant increase in bone mineral density at the lumbar spine and improved bone microarchitecture compared to a placebo (12).

Similarly, in another clinical trial among older adults, supplemental potassium bicarbonate, with mean doses ranging from 2,9 to 4,3mg/day potassium, was administered for 84 days. This supplementation significantly reduced biochemical markers associated with bone turnover and decreased urinary calcium excretion (13).

However, another study found no significant association between potassium supplementation and bone turnover (3). 

Type 2 Diabetes

Several observational studies involving adults have identified associations between lower potassium intake or lower levels of serum or urinary potassium and higher rates of fasting glucose, insulin resistance, and the development of type 2 diabetes (3).

Hypokalemia, characterized by low potassium levels in the blood, can impair insulin secretion from pancreatic cells, potentially leading to glucose intolerance. This effect is often associated with long-term use of diuretics, especially those containing thiazides, or hyperaldosteronism, a condition marked by excessive aldosterone production, both of which increase urinary potassium losses. However, hypokalemia-induced impairment of insulin secretion can also occur in otherwise healthy individuals (3, 14).

Potassium Deficiency 

The usual intake of potassium from naturally occurring nutrients for individuals aged 2 years and older in the US has been found to be 2590mg a day, while adult men require 3500mg and adult women require 2600mg of potassium daily (15).

Potassium deficiency in the blood is known as hypokalemia. It is one of the most frequently encountered electrolyte imbalances in clinical settings. Hypokalemia is more common than hyperkalemia; however, most cases are mild. 

The severity of hypokalemia is typically categorized based on serum potassium levels (16):

  • Mild hypokalemia: Serum potassium level between 3 to 3,4 mmol/L.
  • Moderate hypokalemia: Serum potassium level between 2,5 to 3 mmol/L.
  • Severe hypokalemia: Serum potassium level less than 2.5 mmol/L.


Hypokalemia is commonly associated with medical conditions such as heart disease, kidney failure, malnutrition, and shock. Additionally, hypothermia and conditions involving increased blood cell production, such as leukemia, can also contribute to the development of hypokalemia. 

Certain subsets of patients are particularly susceptible to hypokalemia. For example, psychiatric patients undergoing drug therapy may be at increased risk of developing hypokalemia as a side effect of their medications (16).

Hypokalemia is seldom solely caused by inadequate dietary potassium intake; however, it can occur due to conditions such as diarrhea, where there is a significant potassium loss through stool. Vomiting can also contribute to hypokalemia by inducing metabolic alkalosis, which in turn leads to potassium losses through the kidneys (3).

Low potassium levels can result from impaired absorption, diuretic use, dialysis, and profuse sweating. Thus, people with inflammatory bowel disease (Crohn’s disease and ulcerative colitis) and people on certain medications, such as diuretics and laxatives, are at risk of potassium deficiency (3). 

As mentioned above, increased levels of aldosterone, called hyperaldosteronism, also cause hypokalemia.

Another cause of potassium deficiency is eating clay during a condition called pica. Pica is characterized by persistent and compulsive cravings for non-food items that lack nutritional value. Clay binds to potassium in the gastrointestinal system, inducing potassium excretion.


Clinical symptoms of hypokalemia typically do not become evident until the serum potassium level falls below 3 mmol/L. The severity of these symptoms tends to correlate with the degree and duration of hypokalemia (16). 

Manifestations of hypokalemia primarily affect the musculoskeletal and cardiovascular systems, such as muscle weakness or cramps, fatigue, heart arrhythmias, and palpitations.

The muscle weakness affects the lower limbs first, ascending to the trunk and upper extremities later. Weakness of gastrointestinal muscles leads to nausea, vomiting, and bloating (16).

Low potassium levels cause kidney changes, leading to frequent urination and extensive thirst.

Hypokalemia can indeed lead to glucose intolerance by impairing insulin secretion.

Due to similar causes, low potassium levels often occur along with low magnesium levels.

Potassium Supplements

Potassium supplements are dietary supplements that provide additional potassium to the body. They are typically available in various forms, such as potassium chloride, potassium citrate, potassium gluconate, potassium phosphate, and potassium bicarbonate. These supplements are often used to prevent or treat potassium deficiencies, especially in individuals who may have an increased need for potassium due to certain medical conditions or medications.

Most potassium supplements only provide up to 100mg of potassium per serving.

It's important to note that potassium supplements should only be taken under the guidance of a healthcare professional, as excessive potassium intake can be harmful.

Side Effects of High Potassium and Toxicity

Hyperkalemia or potassium toxicity is defined as having a serum or plasma potassium level above the upper limits of normal, typically greater than 5.0 mmol/L to 5.5 mmol/L. Mild hyperkalemia often presents asymptomatically, but as potassium levels rise, it can lead to potentially life-threatening complications such as cardiac arrhythmias, muscle weakness, or paralysis (17).


Increased potassium levels can result from increased potassium intake, decreased potassium excretion, or potassium storage changes in the body. 

One study showed that fewer than 3% of the population had typical intakes surpassing the recommended potassium allowance (15).

Hyperkalemia causes include infection, dehydration, kidney disease, diabetes, chemotherapy, significant trauma, crush injuries, or muscle pain, indicating rhabdomyolysis (17).

Additionally, certain medications, such as digoxin, potassium-sparing diuretics, non-steroidal anti-inflammatory drugs (NSAIDs), ACE inhibitors, recent IV potassium administration, total parenteral nutrition, potassium penicillin, and succinylcholine, can increase the risk of hyperkalemia (17).


People with chronic hyperkalemia may remain asymptomatic even at increased potassium levels, as their bodies may adapt to the higher potassium levels over time. 

On the other hand, individuals experiencing dramatic and acute shifts in potassium levels may develop severe symptoms even at lower levels. The severity of symptoms can vary depending on factors such as the rate of potassium level change, underlying health conditions, and individual tolerance levels.

Symptoms usually include muscle weakness, fatigue, heart palpitations, arrhythmias, and loss of consciousness (17).

Severe cases of untreated hyperkalemia can lead to heart failure and death.

Interactions With Medications

  • Angiotensin-converting enzyme inhibitors (ACE inhibitors) and angiotensin receptor blockers, such as Captopril, Benazepril (Lotensin), Valsartan, and Losartan, decrease potassium excretion through the kidneys, leading to increased levels of this electrolyte in the blood. 
  • Potassium-sparing diuretics, such as spironolactone (Aldactone, Verospiron) and amiloride (Midamor), elevate potassium levels by reabsorbing potassium into the blood in the kidneys.
  • Loop and thiazide diuretics, such as furosemide (Lasix) and chlorothiazide (Diuril), decrease potassium levels by increasing potassium excretion through the urine.
  • Prolonged and excessive use of non-steroidal anti-inflammatory drugs, such as ibuprofen (Advil) and aspirin (Disprin), can lead to acute kidney injury and secondary hyperkalemia (18).


Potassium is the most abundant positively charged ion in cellular fluid, and it is essential for maintaining normal cell function, particularly in muscle and nervous tissues.

In healthy individuals, approximately 90% of dietary potassium is absorbed in the intestines. 

Potassium is mainly absorbed through passive diffusion in the small intestine. Normal serum potassium concentrations are kept in the range of 3.5 to 5.0 mmol/L.

The recommended intake for potassium is 3400mg for adult men and 2600mg for adult women. These values increase for pregnant (2900mg) and lactating (2800mg) women.

Some foods particularly rich in potassium include potatoes, beans, bananas, oranges, cantaloupes, black strap molasses, beef, turkey, salmon, and tomatoes.

Potassium supplementation can reduce blood pressure, the risk of stroke and cardiovascular disease, and kidney stone development, and improve bone health.

A potassium blood level below 3.5 mmol/L is called hypokalemia, while above 5.0 mmol/L leads to hyperkalemia.

Data provided by should be considered and used as information only. Please consult your physician before beginning any diet.