Why Is Too Much Potassium Bad for You?

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Potassium plays a crucial role in maintaining a balance of fluid in and around all cells. During this balancing act, the mineral transports electricity from cell to cell to make muscles contract and to keep your heart beating. Even though potassium is essential for basic bodily functions, too much leads to hyperkalemia, which causes severe problems.

Irregular Heartbeat

Too much potassium throws the balance of electrolytes off. When this occurs, the natural electrical current in your system gets disrupted, constricting that steady stream of electricity that makes your heart beat. As a result, your pulse weakens, your heart beats erratically and blood flow throughout your body suffers. In severe cases, your abnormal heart rhythm, which is known as arrhythmia, can lead to a heart attack.

Cellular Damage

Most of the potassium in your body is in the fluid inside of cells. As the balance of fluid shifts when you have too much potassium, you could wind up with more pressure inside of cells and not enough on the outside of cells. Picture filling up a balloon to where it exceeds its capacity and is about to burst. The same sort of thing happens to cells. The excessive potassium can cause blood cells to burst, a condition known as hemolysis, which leads to internal bleeding, bruising and poor wound healing. You may even go through organ tissue damage and muscle damage as cells expand or burst.

Neurological Issues

Because cells throughout your system aren’t working properly and electrical flow diminishes when you have too much potassium, you could notice negative neurological effects. Your hands and feet could feel tingly. You can have numbness in your extremities and even very minimal muscle strength to top it off. If you continue to get too much potassium in your system, you might experience paralysis, which is usually temporary until your potassium level returns to normal.

Likelihood of Too Much Potassium

You’re not likely to get too much potassium from your diet, no matter how many potassium-filled fruits, nuts and vegetables you eat. Your multivitamin may have some potassium, although multivitamins in the United States do not contain more than 99 milligrams of potassium in each dose -- far less than the 4,700-milligram daily recommendation, the Linus Pauling Institute states. Taking a separate potassium supplement could be problematic, though, if you take a large dose, possibly leading to a high potassium level. But if you experience adverse effects related to too much potassium in your system and you’re not taking a potassium supplement, it could be a warning sign of a blood disorder, kidney failure, side effect of your medications or other serious ailment.