POTASSIUM

Thousands of years ago, when man roamed the earth gathering and hunting, potassium was abundant in the diet, while sodium was scarce. The so-called Paleolithic diet provided about 16 times more potassium than sodium. Today, most Indians barely get half of the recommended amount of potassium in their diets. 

The increase in sodium to potassium ratio is due to the majority of salt hidden in processed or fast foods. Most of these foods are poor sources of potassium.

This imbalance, which conflicts with human evolution, is thought to be a major contributor to high blood pressure and has affected more than 1/4th of the population globally.

What is the role of potassium in the body?

Potassium is the most abundant intracellular cation in the body. It constitutes 5% of the total mineral content of the body and is present in all body tissues.

Potassium is an electrolyte that helps maintain normal levels of fluids inside the cells.

Potassium is required for:

– normal cell function

– maintaining intracellular fluid volume

– regulating the heartbeat

– proper functioning of the muscles and nerves

– synthesizing protein 

– metabolizing carbohydrates

What is the recommended daily intake of potassium?

Hypertension is a major risk factor for heart diseases. The WHO-based guidelines suggest a decrease in sodium intake and an increase in potassium intake to reduce the risk of high blood pressure and thereby reducing the risk of coronary artery disease, stroke, and cardiovascular diseases.

The recommended dietary allowance in the ICMR 2020, based on WHO (2012) are as follows:

What are the food sources of potassium?

The major sources of potassium are plant foods such as cereals, pulses, fruits, and vegetables. Vegetables such as avocado, broccoli, carrots, peas, lentils, tomatoes, potatoes, and sweet potatoes are good sources of potassium.

Fruits like bananas, apricots, and citrus fruits are rich in potassium.

Milk, milk products, nuts, meat, and fish are other sources of potassium.

Coconut water is one of the richest sources of potassium.

Potassium can be lost while cooking and food processing. All processed foods are poor sources of potassium. A diet rich in processed foods and low in fruits and vegetables is often lacking in potassium.

What are the signs of potassium deficiency in the body?

Normal potassium in the blood ranges from 3.5-5 mM/L. Hypokalemia or low plasma potassium levels can occur with a shift of potassium from the plasma to the cells. This shift can occur in alkalosis. Overall depletion of potassium occurs in vomiting and prolonged fasting. Mild hypokalemia results in weakness and muscle cramps and can cause arrhythmias (irregular heartbeat) in patients with heart diseases. Serve hypokalemia (<2.5 mM/L of potassium) can result in paralysis.

Can high intake of potassium cause toxicity?

High plasma potassium or hyperkalemia occurs when potassium levels are greater than 5 mM/L. Increase blood potassium levels can be due to dehydration, kidney disease, uncontrolled diabetes, and excessive bleeding. Hyperkalemia results in cardiac arrhythmias. A potassium level of 8.0 mM/L can cause cardiac arrest and death. Hyperkalemia can occur in severe kidney diseases where the ability to excrete potassium is impaired especially if potassium consumption is not restricted and the patient is experiencing tissue or RBC breakdown.

Potassium chloride is sometimes present in salt substitutes. This can help replace some or all of the sodium chloride in table salt. Potassium salts have a bitter aftertaste when heated so it is not recommended for cooking. Substituting table salt with a potassium salt may be beneficial to some people.

Check with your doctor before trying a potassium salt, because high potassium can also be harmful. For people who have trouble eliminating excess amounts of potassium or are taking medications that can increase potassium levels in the blood should avoid potassium salts.