You may think that sodium is a “bad guy” that must be avoided or reduced because too much is linked to high blood pressure, but it’s actually an essential electrolyte, a deficiency of which can trigger seizures. Epilepsy is a brain condition defined by seizures, and although most epileptic seizures don’t seem to be caused by low levels of sodium, some might be and others may be made worse by lack of the electrolyte.
Epilepsy is a brain disorder defined by repeated seizures or convulsions. Seizures are triggered by disturbed electrical activity in the brain, which leads to disrupted function, behavior and sensations. Small seizures, traditionally called petit mal seizures, are not always noticeable and may look like a person’s just blanking out for a minute or so. More serious seizures, often called grand mal seizures, usually involve collapse, convulsions and severe muscle spasms that last for a few minutes. There are many causes of epilepsy including head injury, brain tumor, negative reaction to medication, brain toxicity, changes in blood flow and electrolyte or hormonal imbalance. Epilepsy may also have a genetic link.
Sodium is an essential mineral that readily combines with other elements to form salts. Sodium chloride, for example, is common table salt. Once consumed, sodium dissolves in your body fluids and becomes an electrolyte, which means it can conduct electrical current. Electrolytes are essential for conducting electrical messages in the brain and throughout the body via nerves. They are also important for the flow of water into and out of all cells. A chronically low level of sodium, termed hyponatremia, negatively affects the brain and can trigger seizures because it disrupts electrical activity and causes swelling. Hyponatremia can be caused by severe lack of dietary salt, but it’s more often caused by profuse sweating, chronic diarrhea or excessive vomiting. It can also be triggered by kidney disease or negative reactions to medications such as diuretics.
Dietary deficiency of sodium is very rare in the United States because the typical American diet is very high in salt. Most women require about 1,800 milligrams of sodium per day, depending on activity level, health and water intake. To give you a better reference, a teaspoon of table salt contains about 2,000 milligrams of sodium. The best way to determine if you have too much or too little sodium in your system is by a blood test. Normal levels of sodium range between 135 and 145 millimoles per liter of blood.
Seizures from low sodium levels are most likely to occur from a serious disease, acute infection or because you tried to run a marathon on a hot day. One-time or isolated seizures from these causes do not warrant a diagnosis of epilepsy. However, epilepsy is sometimes misdiagnosed and you may have an underlying health condition that is causing an electrolyte problem. Furthermore, a common anti-epileptic medication called oxcarbazepine can reduce your blood-sodium levels with time. Therefore, it’s possible that epilepsy can begin as a condition unrelated to low sodium levels, but later aggravated and triggered by medication that leads to hyponatremia.
- Textbook of Functional Medicine; David S. Jones
- Human Biochemistry; Charles Dreiling
- Human Metabolism: Functional Diversity and Integration; J. Ramsey Bronk
- Compendium of Pharmaceuticals and Specialties; Canadian Pharmacists Association
Sirah Dubois is currently a PhD student in food science after having completed her master's degree in nutrition at the University of Alberta. She has worked in private practice as a dietitian in Edmonton, Canada and her nutrition-related articles have appeared in The Edmonton Journal newspaper.