An often misunderstood and undervalued mineral, potassium is necessary for life. It is the body’s most abundant electrolyte—the word for minerals that carry an electrical charge. Electrolytes play a role in the water balance in the body, as well as the body’s acidity/alkalinity, muscle function and heart rhythm. We lose electrolytes with perspiration, which is why we must consume replacement fluids to prevent serious problems.

Potassium is used for many essential bodily functions, including strong and regular heart contractions, proper kidney function, fluid balance and healthy muscle development. It plays an important role in nerve signaling and increases metabolism to optimally use proteins, fats and carbohydrates for energy. Potassium is important for strong bones, and dietary potassium is closely linked to bone mineral density. This has been demonstrated in several studies, including a 2009 article in Osteoporosis International, looking specifically at post-menopausal women. Though this mineral impacts several areas of health, one of the most far-reaching is its influence on healthy blood pressure, which in turn greatly reduces risk of stroke, transient ischemic attacks (TIAs) and heart attacks.

But potassium can only do its job properly when it’s in optimal balance with the yin to its yang: sodium. Historically, these two minerals were balanced in the diet, as potassium is plentiful in many fruits and vegetables. The ideal ratio, reflected in diets that don’t rely on processed foods, is one part sodium for every seven parts potassium. However, with the introduction of sodium preservatives and easy access to salt, plus the subsequent dietary decline in fresh fruits and vegetables, this natural balance has shifted drastically. By 1995, sodium intake was triple that of potassium according to a study in the American Journal of Physiology. The authors concluded “the relative deficiency of dietary potassium in the modern diet may play a role in the pathology of some chronic diseases.” 

Proper balance is essential because sodium tells the body to hold on to water, and potassium says to let it go. Without adequate potassium, the body retains water, causing increased blood pressure and a whole host of health problems.

In a 2001 study in the Archives of Internal Medicine, researchers reported that American men consume barely 75 percent of the recommended daily intake of 4,700 mg of potassium, and women get only 50 percent. Adding to this deficiency, many prescription and over-the-counter drugs deplete potassium—including decongestants, certain antibiotics, many asthma medications and diuretics.

The name for potassium deficiency is hypokalemia, and it can be diagnosed with a simple blood test. Extreme hypokalemia is an uncommon, life-threatening medical emergency. However, people who are borderline or at the low end of the normal range often exhibit symptoms such as:

• Fatigue
• Muscle weakness, spasms, twitching and painful cramps
• Abnormal sensations like tingling and “pins and needles” in the hands and feet
• Abdominal and gastrointestinal symptoms such as constipation, bloating, fullness and cramping
• Mental confusion and/or depression
• Dry skin

Fruits and vegetables such as oranges, bananas, lima beans, beets, potatoes, melons and tomato products are a few examples of good sources of potassium. Unfortunately, there are obstacles to providing adequate potassium in most dietary supplements. Because potassium is intensely alkaline, it can irritate the lining of the stomach if a tablet or capsule lies in one area and doesn’t dissolve properly. Therefore, the limit that dietary supplements can legally provide is generally less than 100 mg per dose (nowhere near the recommended daily allowance). However, it is available in much higher doses in liquids or drink mixes. 

Improvements in potassium levels can yield excellent health benefits, including reducing blood pressure, eliminating muscle cramps, helping prevent heart attacks and strokes and improving metabolic function. However, there are a few rare conditions (for example, kidney failure) and certain prescription drugs with which potassium intake must be monitored. If you have any questions, talk to your healthcare provider to make sure increasing potassium is right for you.