# What's the significance of high potassium or low potassium levels in the blood? **URL:** \ **Category:** Factual Questions\ **Created:** [February 25, 2008, 4:01am UTC](https://boards.straightdope.com/t/whats-the-significance-of-high-potassium-or-low-potassium-levels-in-the-blood/439043 "2008-02-25T04:01:55Z")\ **Posts on this page:** 4\ **Page:** 1
**Author:** ![Northern\_Piper](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/northern_piper/32/5304_2.png) [@Northern\_Piper](https://boards.straightdope.com/u/Northern_Piper)\ **Post date:** [February 25, 2008, 4:01am UTC](https://boards.straightdope.com/t/whats-the-significance-of-high-potassium-or-low-potassium-levels-in-the-blood/439043/1 "2008-02-25T04:01:55Z")
I’ve got a question about the significance of potassium levels in the blood. What are the effects of a low potassium level? A high potassium level? What does potassium do in the blood, anyway? I’m not asking for any personal reasons, although my curiousity was triggered by health issues of other family members, who are all seeing doctors, etc. One had low potassium levels and was told to eat foods that are rich in potassium, like bananas; another had high levels, and was told to avoid foods that are rich in potassium. Just made me wonder why potassium levels are significant. ---
**Author:** ![Duck\_Duck\_Goose](https://avatars.discourse-cdn.com/v4/letter/d/50afbb/32.png) [@Duck\_Duck\_Goose](https://boards.straightdope.com/u/Duck_Duck_Goose)\ **Post date:** [February 25, 2008, 4:33am UTC](https://boards.straightdope.com/t/whats-the-significance-of-high-potassium-or-low-potassium-levels-in-the-blood/439043/2 "2008-02-25T04:33:20Z")
It helps your nerve and muscle cells to fire. [Fifty-cent explanation:](http://findarticles.com/p/articles/mi_g2601/is_0007/ai_2601000716) > [@](#): > > _Potassium, a necessary electrolyte, facilitates nerve impulse conduction and the contraction of skeletal and smooth muscles, including the heart. It also facilitates cell membrane function and proper enzyme activity. Levels must be kept in a proper (homeostatic) balance for the maintenance of health._ [Low potassium, or hypokalemia.](http://www.nlm.nih.gov/medlineplus/ency/article/000479.htm) [High potassium, or hyperkalemia.](http://www.nlm.nih.gov/medlineplus/ency/article/001179.htm) Short version: slightly low potassium gives you muscle cramps, especially leg cramps, which is why Gatorade and other “re-hydrating” drinks have potassium in them, and really low potassium means your nerve and muscle cells can’t fire and so your heart basically just quits. High potassium skips the leg cramps portion of the program and goes straight to the heart arrhythmia and cardiac arrest. Potassium levels are not something to shrug off when your doctor says “Um”, IOW. If your family member who was told to “eat more bananas” can’t stand bananas, know that [many other food items](http://www.health.gov/dietaryguidelines/dga2005/document/html/appendixB.htm) actually have more potassium in them than bananas. But it’s just easier for the doctor to say, “Eat more nanners” than to say “eat more soybeans, blackstrap molasses, and beet greens.” ---
**Author:** ![masterofnone](https://avatars.discourse-cdn.com/v4/letter/m/4bbf92/32.png) [@masterofnone](https://boards.straightdope.com/u/masterofnone)\ **Post date:** [February 25, 2008, 3:00pm UTC](https://boards.straightdope.com/t/whats-the-significance-of-high-potassium-or-low-potassium-levels-in-the-blood/439043/3 "2008-02-25T15:00:06Z")
A few years back I was clearing land where I was going to build my house. I was working midnight to noon at my regular job, then cutting wood until dark, averaging around 6 hours of running a chainsaw every day. To stay hydrated I usually drank 4 gallons of Gatorade a day. Not a good plan. It was then that I found out I have a short circuit in my heart (SVT), that can be set off by any irregular heartbeat, and that high levels of potassium can cause arrythmia. I’ve switched to water. ---
**Author:** ![Harmonious\_Discord](https://avatars.discourse-cdn.com/v4/letter/h/74df32/32.png) [@Harmonious\_Discord](https://boards.straightdope.com/u/Harmonious_Discord)\ **Post date:** [February 25, 2008, 3:46pm UTC](https://boards.straightdope.com/t/whats-the-significance-of-high-potassium-or-low-potassium-levels-in-the-blood/439043/4 "2008-02-25T15:46:37Z")
The muscle cramp bit is why I’ve told some people to try potassium for night leg cramps. It works for some of the people I know that tried it.