What is Potassium & What Does it Do?

Potassium is an essential mineral and electrolyte.  This is the first time we have used the term electrolyte in our exploration of nutrients, so let’s take a closer look:

Electrolytes: 

An electrolyte is a mineral that can carry an electrical charge when dissolved in water.  Just like the batteries we use to power devices, our cells use positive and negative charges to move electricity (electrons) around.  Instead of copper wiring, our nerves and cell membranes conduct this electricity around our bodies.  We use this electricity to send messages to, from, and throughout our brain and spinal cord.  We also use it to contract muscles, open and close gates in our cell membranes (selectively letting substances in and out of our cells), keep our heart beating, and more. 

The most abundant positive electrolytes (cations) in our body are sodium, potassium, calcium, and magnesium.  Our most abundant negative electrolyte (anion) is chloride.  We need more positive electrolytes than negative because our cells and major proteins are slightly negative in charge. 

Electrons are lost through vomiting, diarrhea, and excessive sweating.  This is why electrolyte beverages can be life-saving in these situations. 

Potassium Deficiency:

Potassium as an electrolyte plays its major role in the body in the firing of nerves and contraction of muscles.  Without enough potassium, these functions are compromised. 

Signs and Symptoms of Potassium Deficiency: (1)

• Fatigue

• Muscle weakness and cramps

• Intestinal paralysis

Causes of Low Potassium: (1)

• Prolonged vomiting or diarrhea

• Laxative abuse

• Potassium wasting diuretic medications

• Excessive sweating

• Eating disorders with purging or restriction components

• Kidney disease

• Excessive urination

• High levels of aldosterone

• Magnesium depletion

• Recovery from prolonged malnutrition 

• Consumption of large amounts of licorice (herb or black licorice candy)

Where to Find Potassium: 

Fruits and vegetables are great sources of potassium with potatoes being the richest source, as long as you eat the skins too.  Nuts, seeds, and dairy products also contain good amounts of potassium. 

Daily Intake:

An RDA has not been set for potassium; however, an AI level has been set.  We can remember that an RDA is the amount of a nutrient needed daily to avoid deficiency, and the AI is the average amount of a nutrient that is consumed by healthy individuals.   The AI for adults ranges from 2,600 - 3,400 mg daily. (1)

Potassium is considered a nutrient of concern as many people in the U.S. do not meet the AI recommendation and because underconsumption is linked to several diseases.  Potassium is most abundant in fruits and vegetables and unfortunately, these foods are underconsumed in the U.S. population.  

Before we jump to judgment, we must remember that some people choose not to eat fruits and vegetables while others don’t even have the choice.  If you have access to a grocery store, CSA, farm stand, or backyard garden, please remember that this is a privilege not available to everyone.  Food justice is social justice, and we have a long way to go here in the US!

Toxicity:

High levels of potassium in the blood, hyperkalemia, can lead to abnormal heart rhythms that can cause cardiac arrest.  Other less deadly symptoms include tingling of the hands and feet, muscle weakness, and temporary paralysis. (1) 

Causes of hyperkalemia include: (1)

• Kidney failure (acute or chronic)

• Use of potassium sparing diuretics

• Low aldosterone levels

• High doses of potassium (>18 g)

• Breakdown of blood cells in the body (hemolysis)

• Severe burns

• Severe physical injury

Prevention and Treatment of Disease:

Consuming adequate levels of potassium combined with lowering sodium levels is associated with lower risk of stroke, kidney stones, and osteoporosis. (1)

When it comes to disease treatment, potassium plays a role in lowering elevated blood pressure. 

Medication and Nutrient Interactions:

There are many!

Medications that can cause hyperkalemia (high potassium): (1)

• ACE inhibitors (the -pril drugs)

• ARBs (the -sartan drugs)

• Heparin

• Beta and alpha blockers

• Trimethoprim-sulfamethoxazole

• Pentamidine

• Digitalis

• Indomethacin

• Ibuprofen

• Ketorolac

• Spironolactone

• Amiloride

• Triamterene

Medications that can cause hypokalemia (low potassium): (1)

• Amikacin

• Gentamicin

• Kanamycin

• Tobramycin

• Streptomycin

• Penicillins

• Tetracyclines

• Cisplatin

• Amphotericin B

• Fluconazole

• Albuterol

• Bitolterol

• Metaproterenol

• Loop diuretics

• Thiazide diuretics

• Mineralocorticoids (prednisone)

• Methylxanthines

• Sodium polystyrene sulfonate

• Sodium phosphates

• caffeine

Applications:

This week, I hope you walk away with these key points: 

1. Potassium is an important mineral and electrolyte.

2. Low potassium and high potassium both have detrimental and even life threatening effects.

3. Most people in the U.S. do not get enough potassium.

4. Potassium is found abundantly in fruits and vegetables. 

5. There are many medications that can cause low or high potassium levels.  Be sure to talk with your doctor about your medications and how to watch for and prevent potassium issues. 

Next week: 

Next week we will explore selenium and its roles in oxidative stress, thyroid function, immune function, and even the development of sperm!  We only have three more minerals to go!  I will be taking a break after that to enjoy a Spring Break road trip with my sweetheart and look at big rocks, petroglyphs, and dinosaur tracks.  On my return, I will work on a few articles to help us put these many pieces together.  Information is great, but we need concrete ways to make use of it!

To our health!

References: 

1. Higdon, J, “Potassium” Linus Pauling Institute, 2001; last update: 2019; accessed January 27, 2022; https://lpi.oregonstate.edu/mic/minerals/potassium