1. Lowers Blood Pressure and Supports Heart Health
As an electrolyte, potassium helps to control the electrical activity of the heart that regulates blood pressure, circulation and heart beat rhythms. Many studies have found that a diet that is low in potassium but high in sodium foods can be a contributing factor to high blood pressure, hypertension and cardiovascular disease. (16)
This is because potassium, in combination with other minerals like calcium and magnesium, prevents fluid from building up in cells. A buildup of fluid within cells is what elevates blood pressure and can result in heart palpitations, narrowed arteries, scarring and poor circulation. Low potassium can also contribute to an irregular heartbeats, chest pains and cardiac arrest when the situation becomes worsened over time, so making sure to consume plenty of potassium-rich foods while also limiting excess sodium is important for maintaining heart health, especially into older age. (17)
2. Supports a Healthy Metabolism
Potassium is needed to maintain and even boost your metabolism because it’s partially responsible for breaking down carbohydrates, in the form of glucose, from the foods we eat and turning them into useable energy. Additionally, potassium helps the body to use amino acids in order to form proteins that build muscle.
Following exercise, many athletes choose to consume potassium-rich foods like orange juice, a banana or a potato in order to replace the potassium lost during exercise. Potassium can also help balance minerals within the body that are important for growth and maintenance of both muscles and bones.
3. Prevents Muscle Spasms and Pain
By balancing fluid levels, potassium helps the muscles to relax, so low potassium can result in muscle spasms, cramps and general pains. Because of how it’s used to help breakdown carbs and proteins that muscles rely on for energy and repair, low potassium can also cause a breakdown of muscle mass, fatigue, trouble exercising and can even possibly contribute to weight gain.
4. Helps Maintain Bone Health
Potassium is needed to help protect bones from becoming weak and prone to breaks or fractures. In the body, potassium forms conjugate anions such as citrate that are converted to bicarbonate. Low potassium levels are associated with reduced bicarbonate precursors that are needed to neutralize acids that are present in commonly eaten foods, especially animal proteins.
Sulfuric acids enter the body in the form of the amino acids found in meat, poultry and other high-protein foods. Since low potassium means low levels of bicarbonate precursors, the bones are not properly buffered from the effects of sulfer-acids and can become demineralized, weak and porous when someone’s diet is lacking in potassium. This can increase the risk for osteoporosis and fractures.
5. Supports the Nervous System
Because potassium is involved in thousands of cellular functions day in and day out, it’s crucial for nerve impulses and electrical signaling that brain functions rely on. Deficiency in potassium can cause fatigue, poor concentration, trouble learning and remembering, and mood changes.
In fact, one of the biggest signs of low potassium is “brain fog,” or the inability to focus and keep a clear-headed, upbeat mood.
6. Needed for Proper Digestion
Potassium acts like an electrolyte, helping to balance water, fluid and sodium levels within the digestive tract. Low potassium can contribute to bloating, constipation or abdominal pain in some cases because fluids build up and cause imbalances in minerals.
It’s also partially responsible for balancing the amount of acid in the stomach, healing the gut and keeping the body at the optimal pH level. This allows healthy bacteria to thrive and kill off harmful bacteria that lower immunity.
7. Prevents Kidney Disorders
A higher potassium intake can help lower the risk for kidney stone formation. Studies have shown that people prone to kidney stones usually have diets higher in sodium and lower in potassium.
Low potassium levels are also associated with an increased risk for kidney stones due to the inverse relationship between potassium and calcium. When someone has low potassium levels, an excess amount of calcium is excreted from the body through urine, which must pass through the kidneys. In many instances, kidney stones are actually calcium deposits, so reducing calcium in the urine is one way to fight off painful kidney problems. (18)
Do You Need Potassium Supplements?
Potassium supplements usually aren’t recommended for normal, healthy adults. They are given under certain conditions to people who have disorders that stop them from absorbing potassium effectively, but otherwise it’s advised to get potassium from real food sources first and foremost.
In some cases there is such thing as “too much of a good thing.” High potassium levels can cause complications just like low potassium can. Because potassium balance relies on healthy kidney function, but many people suffer from somewhat impaired kidney function as they age, potassium supplements are sometimes considered dangerous.
People with diabetes, a history of heartfailure, taking anti-hypertension drugs and even commonly taking pain relievers such as aspirin and ibuprofen can experience high potassium levels that disrupt mineral balance if they consume potassium supplements regularly.
To be cautious, the Food and Drug Administration (FDA) limits over-the-counter potassium supplements (including multivitamin/mineral pills) to less than 100 milligrams, which is equal to about 2 percent of the recommended 4,700 milligrams a day for adults.
In general, in healthy adults that have normal kidney function, potassium intake from foods alone doesn’t pose much of a risk for negative side effects because excess potassium is excreted in the urine. However, for people who have abnormal kidney function or who take potassium supplements in high doses, negative side effects are possible.
Interactions of Potassium
Too much potassium in the blood is known as hyperkalemia (the opposite of very low potassium levels of hypokalemia). Excessively high potassium can cause dangerous changes to heart rhythms in addition to other risks like blood pressure changes and weakness.
Here are 12 of the best food sources of potassium:
(Percentages based on the recommended daily value of 4,700 milligrams for adult men and women.)
Elderly people and anyone with kidney disorders, diabetes, chronic renal insufficiency, severe heart failure or adrenal insufficiency are more at risk for having high potassium. People with kidney problems, especially those on dialysis, should definitely be careful not to take potassium supplements or even to eat too many potassium-rich foods without speaking with their doctor.