What is the Connection Between Leg Cramps and Potassium?

Leg cramps are painful muscle contractions which can last a couple of seconds or as long as several minutes. Several factors contribute to leg cramps, but one of the most common causes is a deficiency of potassium. The connection between leg cramps and potassium can be understood by looking at the physiology of the muscle cell, medical conditions which cause both leg cramps and potassium deficiency, and the role of potassium in preventing leg cramps.

When a muscle contracts, sodium ions leave the muscle cell through specialized channels, and potassium ions enter the cell. If there is only a small amount of potassium ions, then relaxation of the muscle will be delayed. The result is a prolonged contraction of the muscle, causing sharp muscle pain and cramping.

Potassium deficiency is typically the result of heath issues rather than poor diet. Several medical conditions, including dehydration and treatments for constipation, involve potassium deficiency. Doctors often check for one of these medical issues if a patient reports leg cramping.

Extreme exertion during physical activity, hot weather, and not drinking enough fluids are the most common causes of dehydration. Illnesses associated with vomiting and diarrhea may also lead to dehydration. Dehydration quickly depletes the body of essential minerals like potassium, and can lead to muscle cramps. Muscle cramps caused by extreme exercise, enduring high temperatures, or suffering from intestinal illnesses can be avoided by drinking plenty of water or other fluids rich in minerals, such as orange juice or sports drinks.

Long-term laxative use is often associated with leg cramps, and potassium deficiency brought on by laxative use is often the cause. Laxatives relieve constipation by using water in the body to soften stool and help it pass. The laxatives cause the water to be extracted from the body relatively fast, carrying away important minerals, such as potassium. Discontinuing the laxative, taking them for only a short time, or taking them with lots of water may relieve any cramping associated with laxative use.

If a patient suffers from leg cramps but has not used laxatives or experienced dehydration, a doctor may suggest trying to moderately increase potassium intake to see if it relieves the cramping. Potassium supplements are available, and should certainly be taken if suggested by a doctor. There are many foods rich in potassium which can be eaten to increase potassium in the body and relieve leg cramps. Fruits highest in potassium are apricots, raisins, figs and bananas. Potatoes, tomatoes, spinach and squash are vegetables high in potassium, and meats rich in potassium include poultry and fish.