Potassium is the third most abundant mineral in your body, and plays an important role in several body processes (1).
However, very few people consume enough of it. In fact, nearly 98% of all adults in the US are not meeting the daily intake recommendations (2).
This article will tell you how much potassium you need per day, as well as why it’s important for your health.
What Is Potassium?
Potassium is an incredibly important mineral and electrolyte. It’s found in a variety of whole foods, including leafy vegetables, legumes and fish, such as salmon.
About 98% of the potassium in your body is found inside cells. Of this, 80% is found inside muscle cells, while 20% is in bone, liver and red blood cells (3).
Summary: Potassium is an important mineral and electrolyte. It is involved in muscle contractions, heart function and regulating water balance.
Is Deficiency Common?
Unfortunately, most adults don’t consume enough potassium (2).
In many countries, a Western diet is often to blame, likely because it favors processed foods, which are poor sources of this mineral (11).
However, just because people aren’t getting enough doesn’t mean they’re deficient.
A potassium deficiency, also known as hypokalemia, is characterized by a blood level of potassium less than 3.5 mmol per liter (12).
Surprisingly, deficiencies are rarely caused by a lack of potassium in the diet (13).
They usually occur when the body loses too much potassium, such as with chronic diarrhea or vomiting. You may also lose potassium if you’re taking diuretics, which are medications that cause your body to lose water (14, 15).
Symptoms of deficiency depend on your blood levels. Here are the symptoms for three different levels of deficiency (12):
- Mild deficiency: When a person has blood levels of 3–3.5 mmol/l. It usually does not have symptoms.
- Moderate deficiency: Happens at 2.5–3 mmol/l. Symptoms include cramping, muscle pain, weakness and discomfort.
- Severe deficiency: Happens at less than 2.5 mmol/l. Symptoms include irregular heartbeat and paralysis.
Summary: A potassium deficiency is uncommon. However, most adults are not consuming enough of this important mineral.
The Best Dietary Sources of Potassium
The best way to increase your potassium intake is through your diet.
Potassium is found in a variety of whole foods, especially fruits and vegetables.
Due to the insufficient evidence behind the mineral, nutrition experts haven’t determined a Reference Daily Intake (RDI).
An RDI is the daily amount of a nutrient likely to meet the needs for 97–98% of healthy people (16).
Below are some foods that are excellent sources of potassium, as well as how much they contain in a 3.5-ounce (100-gram) serving (17):
- Beet greens, cooked: 909 mg
- Yams, baked: 670 mg
- White potatoes, baked: 544 mg
- Soybeans, cooked: 539 mg
- Avocado: 485 mg
- Sweet potato, baked: 475 mg
- Spinach, cooked: 466 mg
- Edamame beans: 436 mg
- Salmon, cooked: 414 mg
- Bananas: 358 mg
Summary: A variety of whole foods are excellent sources of potassium, including beet greens, yams, potatoes and spinach.
Health Benefits of Potassium
A diet rich in potassium is associated with some impressive health benefits. It may prevent or alleviate a variety of health problems, including:
- High blood pressure: Many studies have shown that potassium-rich diets can lower blood pressure, especially for people with high blood pressure (8, 18, 19).
- Salt sensitivity: People with this condition may experience a 10% increase in blood pressure after eating salt. A potassium-rich diet may eliminate salt sensitivity (20, 21).
- Stroke: Several studies have shown that a potassium-rich diet may reduce the risk of stroke by up to 27% (22, 23, 24, 25).
- Osteoporosis: Studies have shown that a potassium-rich diet may help prevent osteoporosis, a condition associated with porous bones (9, 26, 27, 28).
- Kidney stones: Studies have found that potassium-rich diets are associated with a significantly lower risk of kidney stones than diets low in this mineral (10, 29).
Summary: A diet rich in potassium may alleviate high blood pressure and salt sensitivity and may reduce the risk of stroke. Additionally, it may help prevent osteoporosis and kidney stones.
How Much Should You Consume Per Day?
Your daily potassium needs can depend on a variety of factors, including your health status, activity level and ethnicity.
These organizations include the World Health Organization (WHO), and countries including the UK, Spain, Mexico and Belgium.
Other countries, including the US, Canada, South Korea and Bulgaria, recommend consuming at least 4,700 mg per day through food (7).
However, there are several groups of people who may benefit more than others from meeting the higher recommendation. These people include:
- Athletes: Those who partake in long and intense exercise may lose a significant amount of potassium through sweat (15).
- African Americans: Studies have found that consuming 4,700 mg of potassium daily can eliminate salt-sensitivity, a condition more common among people of African American descent (20).
- High-risk groups: People at risk of high blood pressure, kidney stones, osteoporosis or stroke may benefit from consuming at least 4,700 mg of potassium per day (10, 18, 22, 26).
In short, aim to consume 3,500–4,700 mg of this mineral per day from foods. People who need more potassium should aim towards the higher end.
Summary: A healthy adult should aim to consume 3,500–4,700 mg of potassium daily from foods. Certain groups of people should aim to consume at least 4,700 mg per day.
Should You Take Supplements?
Surprisingly, potassium supplements are usually not great sources of this mineral.
The US Food and Drug Administration (FDA) limits over-the-counter potassium supplements to less than 100 mg per serving — just 2% of the US daily recommendation (31).
The amount in over-the-counter supplements is likely restricted due to the risks of overdosing.
Taking too much of this mineral can cause excess amounts to build up in the blood, which is known as hyperkalemia. In some cases, this may cause an irregular heartbeat, called cardiac arrhythmia, which can be fatal (32, 33).
However, people who are deficient or at risk of deficiency may require a high-dose potassium supplement. In these cases, doctors may prescribe a higher-dose supplement and monitor you for any reactions.
Summary: Potassium supplements are not necessary for a healthy adult. However, some people are prescribed a higher-dose supplement.
How Much Is Too Much?
An excess of potassium in the blood is known as hyperkalemia. The condition is characterized by a blood level higher than 5.0 mmol per liter, and can be dangerous.
For a healthy adult, there is no significant evidence that potassium from foods can cause hyperkalemia (16).
For this reason, potassium from foods does not have a tolerable upper intake level. This is the most a healthy adult can consume in a day without adverse effects (6).
Hyperkalemia generally affects people with poor kidney function, or people who take medications that may affect kidney function.
This is because excess potassium is mainly removed by the kidneys. Therefore, poor kidney function may result in a buildup of this mineral in the blood (36).
Compared to foods, potassium supplements are small and easy to take. Taking too many at once may overwhelm the kidneys’ ability to remove excess potassium (39).
Additionally, there are several groups of people who may need less of this mineral than others, including:
- People with chronic kidney disease: This disease increases the risk of hyperkalemia. People with chronic kidney disease should ask their doctor how much potassium is right for them (40, 41).
- Those taking blood pressure medications: Some blood pressure medications, such as ACE inhibitors, may increase the risk of hyperkalemia. People taking these medications may need to watch their potassium intake (42, 43).
- Elderly people: As people age, their kidney function declines. Elderly people are also more likely to take medications that affect the risk of hyperkalemia (44, 45).
Summary: It is difficult for a healthy adult to overdose on potassium from foods. However, people with kidney problems, as well as the elderly and those who take medications for blood pressure, may need less potassium.
The Bottom Line
Potassium is an essential mineral and electrolyte that’s involved in heart function, muscle contraction and water balance.
A high intake may help reduce high blood pressure, salt sensitivity and the risk of stroke. Additionally, it may protect against osteoporosis and kidney stones.
Despite its importance, very few people around the world get enough potassium. A healthy adult should aim to consume 3,500–4,700 mg daily from foods.
To increase your intake, incorporate a few potassium-rich foods into your diet, such as spinach, beet greens, potatoes and fish, such as salmon.