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What is potassium?

Potassium is the third most abundant mineral in the body.

It helps the body regulate fluids, send nerve signals and regulate muscle contractions.

About 98% of the potassium in the body is found in cells. Of these, 80% are found in muscle cells, while the other 20% are found in bones, liver, and red blood cells.

Once in your body, it acts as an electrolyte.

When in water, electrolytes dissolve into positive or negative ions that have the ability to conduct electricity. Potassium ions have a positive charge.

Your body uses this electricity to manage a variety of processes, including fluid balance, nerve signals, and muscle contraction.

Thus, having low or high levels of electrolytes in the body can affect many critical functions.

It helps regulate body fluid balance

The body is made up of approximately 60% water.

40% of this water is found inside cells in a substance called intracellular fluid (ICF).

The rest is outside the cells in the blood, spinal fluid, and between cells. This fluid is called extracellular fluid (ECF).

Interestingly, the amount of water in ICF and ECF is affected by the concentration of electrolytes, especially potassium and sodium.

Potassium is the main electrolyte in ICF and determines the amount of water within the cell. In contrast, sodium is the primary electrolyte in the ECF, which determines the amount of water outside the cells.

The amount of electrolyte relative to the amount of liquid is called osmotic pressure. Under normal circumstances, the osmotic pressure inside and outside the cell is the same.

In short, electrolyte balance inside and outside the cell.

However, when the osmotic pressures are not equal, water from the side with less electrolytes will flow into the side with more electrolytes to balance the electrolyte concentration.

This can cause the cells to shrink as water flows out, or to swell and rupture as water enters the cells.

That's why it's important to make sure you're getting the right electrolytes, including potassium.

Maintaining a good fluid balance is important for optimal health. Poor fluid balance can lead to dehydration, which can affect the heart and kidneys.

Eating a potassium-rich diet and staying hydrated can help maintain a good fluid balance.

Potassium is important for the nervous system

The nervous system carries messages between your brain and body.

This information is transmitted in the form of nerve impulses that help regulate muscle contractions, heartbeat, reflexes and many other body functions.

Interestingly, nerve impulses are generated by sodium ions entering the cell and potassium ions leaving the cell.

The movement of ions changes the cell's voltage, activating nerve impulses.

Unfortunately, reduced levels of potassium in the blood can affect the body's ability to generate nerve impulses.

Getting enough potassium from your diet can help you maintain healthy nerve function.

Potassium helps regulate muscle and heart contractions

The nervous system helps regulate muscle contractions.

However, changes in blood potassium levels can affect nerve signals in the nervous system and weaken muscle contractions.

Both low and high blood levels can affect nerve impulses by changing the voltage of nerve cells.

This mineral is also important for a healthy heart because it moves in and out of cells to help maintain a normal heartbeat.

When blood levels of minerals are too high, the heart may dilate and relax. This weakens its contractions and produces abnormal heartbeats.

Similarly, low levels in the blood can also alter the heartbeat.

When the heart cannot beat properly, it cannot effectively pump blood to the brain, organs, and muscles.

In some cases, arrhythmias, or irregular heartbeats, can be fatal and lead to sudden death.

Health Benefits of Potassium

Consuming a potassium-rich diet is associated with many impressive health benefits.

May help lower blood pressure

Hypertension affects nearly one-third of Americans.

It is a risk factor for heart disease, the leading cause of death worldwide.

A diet rich in potassium can lower blood pressure by helping the body get rid of excess sodium.

High sodium levels can raise blood pressure, especially in people whose blood pressure is already high.

An analysis of 33 studies found that when people with high blood pressure increased their potassium intake, their systolic blood pressure dropped by 3.49 mmHg and their diastolic blood pressure dropped by 1.96 mmHg.

In another study that included 1,285 participants aged 25-64, scientists found that people who consumed the most potassium had lower blood pressure than those who consumed the least.

Those who consumed the most had an average systolic blood pressure drop of 6 mmHg and a diastolic blood pressure drop of 4 mmHg.

May help prevent stroke

Stroke occurs when there is insufficient blood flow to the brain. It is the cause of death for more than 130,000 Americans each year.

Several studies have found that eating a diet rich in potassium may help prevent stroke.

In an analysis of 33 studies including 128,644 participants, scientists found that people with the highest potassium intake had a 24 percent lower risk of stroke than those with the lowest intake.

Additionally, an analysis of 11 studies with 247,510 participants found that those with the highest potassium intake had a 21 percent lower risk of stroke. They also found that eating a diet rich in this mineral was associated with a lower risk of heart disease.

May help prevent osteoporosis

Osteoporosis is a disease characterized by hollow and porous bones.

It is often associated with low levels of calcium, an important mineral for bone health.

Interestingly, research shows that a diet rich in potassium can help prevent osteoporosis by reducing how much calcium the body loses through urine.

In a study of 62 healthy women aged 45-55, scientists found that those with the highest potassium intake had the greatest total bone mass.

In another study of 994 healthy premenopausal women, scientists found that those who ate the most potassium had more bone mass in the bones of their lower back and hips.

May help prevent kidney stones

Kidney stones are clumps of material that may form in concentrated urine.

Calcium is a common mineral found in kidney stones, and several studies have shown that potassium citrate can reduce calcium levels in urine.

In this way, potassium may help fight kidney stones.

Many fruits and vegetables contain potassium citrate, making it easy to add to your diet.

In a four-year study of 45,619 men, scientists found that those who consumed the most potassium each day had a 51 percent lower risk of developing kidney stones.

Similarly, in a 12-year study of 91,731 women, scientists found that those who consumed the most potassium each day had a 35 percent lower risk of developing kidney stones.

It may reduce water retention

Water retention occurs when too much fluid accumulates in the body.

Historically, potassium has been used to treat water retention.

Research shows that high potassium intake can help reduce water retention by increasing urine output and lowering sodium levels.

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