Sodium and Potassium Balance
The easiest way to throw your sodium-potassium ratio off kilter is by consuming a diet of processed foods, which are notoriously low in potassium while high in sodium. (Processed foods are also loaded with fructose, which is clearly associated with increased heart disease risk, as well as virtually all chronic diseases.) Your body needs potassium to maintain proper pH levels in your body fluids, and it also plays an integral role in regulating your blood pressure. As indicated in the PURE study, potassium deficiency may be more responsible for hypertension than excess sodium. Potassium deficiency leads to electrolyte imbalance, and can result in a condition called hypokalemia. Symptoms include:
- Water retention
- Raised blood pressure and hypertension
- Heart irregularities/arrhythmias
- Muscular weakness and muscle cramps
- Continual thirst and constipation
According to a 1985 article in The New England Journal of Medicine, titled “Paleolithic Nutrition,24” our ancient ancestors got about 11,000 milligram (mg) of potassium a day, and about 700 mg of sodium. This equates to nearly 16 times more potassium than sodium. Compare that to the Standard American Diet where daily potassium consumption averages about 2,500 mg (the RDA is 4,700 mg/day), along with 3,600 mg of sodium. This may also explain why high-sodium diets appear to affect some people but not others.
According to a 2011 federal study into sodium and potassium intake, those at greatest risk of cardiovascular disease were those who got a combination of too much sodium along with too little potassium. The research, published in the Archives of Internal Medicine,25 was one of the first and largest American studies to evaluate the relationship of salt, potassium, and heart disease deaths. Tellingly, those who ate a lot of salt and very little potassium were more than twice as likely to die from a heart attack as those who ate about equal amounts of both nutrients.
Low potassium level
Hypokalemia, also spelled hypokalaemia, is a low level of potassium (K+) in the blood serum. Normal potassium levels are between 3.5 and 5.0 mmol/L (3.5 and 5.0 mEq/L) with levels below 3.5 mmol/L defined as hypokalemia. Mildly low levels do not typically cause symptoms. Symptoms may include feeling tired, leg cramps, weakness, and constipation. It increases the risk of an abnormal heart rhythm such as bradycardia and cardiac arrest.
Causes of hypokalemia include diarrhea, medications like furosemide and steroids, dialysis, diabetes insipidus, hyperaldosteronism, hypomagnesemia, and not enough intake in the diet. It is classified as severe when levels are less than 2.5 mmol/L. Low levels can also be detected on an electrocardiogram (ECG). Hyperkalemia refers to a high level of potassium in the blood serum.
The speed at which potassium should be replaced depends on whether or not there are symptoms or ECG changes. Mildly low levels can be managed with changes in the diet. Potassium supplements can be either taken by mouth or intravenously. If given by intravenous, generally less than 20 mmol are given over an hour. High concentration solutions (>40mmol/L) should be given in a central line if possible. Magnesium replacement may also be required.
Hypokalemia is one of the most common water–electrolyte imbalances. It affects about 20% of people admitted to hospital. The word “hypokalemia” is from hypo- means “under”; kalium meaning potassium, and -emia means “condition of the blood”.