A muscle spasm is a condition in which the muscle contracts against a person's will without relaxing. Muscle cramps are common, and often a person can relieve the cramp simply through stretching the contracting muscle. Muscle spasms occur most often when a muscle is damaged or overused. But muscle spasms may also occur because of low levels of the electrolyte potassium. Increasing potassium can decrease the occurrence of muscle spasms but can be dangerous if not done with a physician's supervision.
Identification
During a muscle spasm, muscles often feel tight or knotted and, in some cases, the pain is severe. It is common for people to experience muscle spasms after working out or even from stress. A person with a back injury may experience muscle spasms because of irritation of the spinal nerves. In some cases, deficiencies in electrolytes or minerals such as potassium and calcium can cause them, notes the National Institutes of Health.
Function
Potassium is essential for nerve and muscle cell function. As an electrolyte, it conducts electrical impulses throughout the body. Normal blood potassium levels should be between 3.5 and 5.0 milliequivalents per liter, or mEq/L. When potassium levels are low, electrical impulses throughout the body can fail, causing muscle spasms and weakness. When potassium levels become dangerously low, falling below 3.5 mEq/L, people can experience abnormal heart rhythms, breakdown of muscle fiber, fatigue, paralysis and death.
Food Sources
People with recurring muscle cramps may want to increase their potassium levels by consuming more potassium-rich foods. The U.S. Department of Agriculture's recommended daily amount of potassium for adults is 1,600 to 2,000 mg. Good sources of potassium include sweet potatoes, tomato paste, white potatoes, beet greens, yogurt, clams, prune and carrot juice, tuna, lima beans, bananas and halibut.
Supplements
It is best to try to get adequate amounts of potassium through food sources, but over-the-counter potassium supplements are available. Potassium supplements come in tablet, powder, capsule and liquid form. They can interact with a number of medications, so people should speak with their physician or pharmacist before taking a potassium supplement on their own. Side effects of potassium supplements can include slow or irregular heartbeat; numbness in the hands, feet and lips; unexplained anxiety; weakness; and heaviness in the legs, according to MayoClinic.com.
Warning
While muscle spasms can be painful, they're generally rare and short-lived. People experiencing recurrent muscle cramps should consult their physician to find out whether they're experiencing low serum potassium levels, as this can indicate an underlying condition. Patients should not take more than the recommended daily allowance for potassium supplements, because high levels of potassium can also be life-threatening.
