Potassium is a mineral that is used by the body cells to create an electrical conduction system across the cell membrane. These cell membrane transmissions promote heart function, nerve impulse transmissions and muscle contractions. Potassium has been associated with the prevention of stroke, osteoporosis and kidney stones, as well as the treatment of high blood pressure. Too little potassium, called hypokalemia, may affect sleep patterns.
Potassium and Hypokalemia
You should be able to eat enough potassium-containing foods to maintain a normal blood level; any excess potassium will be excreted by the kidneys. Some medications, especially diuretics, can cause you to excrete too much potassium. Vomiting, diarrhea, eating disorders and the excessive use of licorice can also contribute to hypokalemia. A slight decrease usually doesn't cause symptoms, but if symptoms are present, they tend to take the form of abnormal heart rhythms, fatigue and muscle spasms. Muscle spasms in particular may disrupt sleep.
Potassium is an electrolyte, a substance that can break down into particles called ions. Ions carry an electrical charge, and electrolytes are capable of conducting electricity. Potassium is the major ion inside the body cells – the concentration of potassium inside a cell is about 30 times higher than the concentration outside. Sodium, another electrolyte, is higher outside the cell. The differences in electrolyte concentrations allow a tiny system known as a potassium-ATP pump to move potassium into the cell.
Potassium Channels and Sleep
According the May 26, 2007, "Science Daily," research on a sleep gene in fruit flies indicates specific genes help to control the flow of potassium into the cells. Since similar potassium channels are present in both fruit flies and humans, the researchers theorized that potassium channels help generate sleep in both species. If potassium channels are defective or absent, so are slow waves – oscillations across the brain that indicate deep sleep. A study in the August 1991 "Sleep" reports that potassium supplementation increased sleep efficiency and reduced episodes of waking after sleep onset.
Although there is no definitive research to support the concept that low potassium causes sleep problems, the potential is there. Potassium channel dysfunctions, which can prevent potassium from getting into cells, and the muscle spasms, which are one of the symptoms of hypokalemia, could both disrupt your sleep. If you have a chronic problem with insomnia or feel tired all the time, consult a health care professional – insomnia and fatigue can be symptoms of serious disorders such as sleep apnea.
- MedLine Plus; Hypokalemia; David C. Dugdale, III, M.D. and David Zieve, M.D.; May 2011
- The Linus Pauling Institute; Potassium; Jane Higdon, Ph.D., et al.; December 2010
- “Sleep”; M.D. Drennan, et al.; Potassium Affects Actigraph-Identified Sleep; August 1991
- “ScienceDaily”; Second Sleep Gene Identified; May 26, 2007