Dietary potassium protects against atherosclerosis

Atherosclerosis is one of the leading causes of death in the Western world, and the heart is particularly vulnerable. According to a study from the University of Birmingham, Alabama (USA), foods that are rich in potassium such as bananas, potatoes, avocado, and almonds protect against this disease, which takes years to develop. Beware that too much salt and the use of diuretics may deplete the body’s potassium stores.

Atherosclerosis is caused by deposits of oxidized cholesterol and fat on the inside of the arterial walls. This results in thickening of the vessel walls. The blood supply eventually decreases, and blood platelets are more likely to cause a clot (thrombosis). Atherosclerosis affects all people sooner or later, but only few have actual symptoms. The changes are mainly seen in aorta and in the arteries of the brain, kidneys, and legs, but they may also occur in all large and mid-sized arteries. Atherosclerosis causes arterial stiffness, and the arteries lose their elasticity. To compensate for this, the heart must work harder, and that makes your blood pressure go up.

Lack of potassium may cause artery stiffness and atherosclerosis

In their study from University of Birmingham, Alabama, the American scientists found not only that plenty of dietary potassium helps prevent atherosclerosis, they also discovered that a high intake of potassium helps reduce atherosclerosis and stiff arteries. They also revealed molecular mechanisms that occur when dietary intake of potassium is either low or high.
In their study, the scientists used live mice and fed them different amounts of dietary potassium. The researchers also took out cells and smooth muscle tissue cells from the arteries of the mice, which they cultivated in a growth medium and studied
It turned out that the mice who got a diet with small quantities of potassium had significantly stiffer arteries and more atherosclerosis than the mice who got more potassium.
The researchers measured pulse wave velocity (PWV) in the living mice. PWV is the speed at which the arterial pulse propagates through the cardiovascular system. Pulse wave velocity is used as a clinical measure for arterial stiffness.
By studying the cell cultures, the researchers were able to see how levels of potassium determined both pulse wave velocity and calcification of the cells.

Biochemical details

Lead researcher, Professor Yabing Chen, and his colleagues showed that the smooth muscle cells of the arteries end up looking like bone cells when they calcify. The researchers also found that conditions with low potassium levels altered the genetic expression of the smooth muscle tissue from arteries, giving them the same characteristics as those observed in bone cells.
They saw that potassium deficiency increased the uptake of calcium in the smooth muscle cells via their calcium channels. This process was accompanied by several other biochemical processes (CREB and autophagy), which contribute to arterial stiffness and atherosclerosis.
Afterwards, the team of scientists tested on the live mice how a diet with more potassium is able to control atherosclerosis by means of calcium signaling and other biochemical processes.

Make sure to get enough potassium and beware of things that deplete your potassium levels

The knowledge about how (smooth) muscle cells in the arteries control atherosclerosis underlines the necessity of getting enough potassium to prevent artery stiffness and atherosclerosis. The results of this study shows new paths in the treatment of these conditions. It is important to get enough dietary calcium and to be able to identify those factors that make us lose potassium.

Potassium sources and things that deplete your potassium levels

Bananas, potatoes, avocado, beans, almonds, apples, and other types of fruit and vegetables contain a lot of potassium. Seaweed is a particularly rich source. However, our modern, refined diet that consists mainly of grain, meat, and dairy products has resulted in a lower potassium intake. The problem is made worse by our growing intake of sodium (salt) from sources like table salt, cheese, chips, cold cuts, ready meals, and other types of industrially processed food. Too much sugar, coffee, alcohol and the use of diuretics may also deplete our potassium levels. Stress also adds to the problem through the adrenal hormone, aldosterone, which retains sodium and excretes potassium.

Potassium content in mg per 100 grams

• Seaweed 7,500
• White beans 1,530
• Almonds 725
• Avocado 450
• Potato 414
• Beetroot, salmon 330

Important note: Atherosclerosis is about more than cholesterol

As shown in the new American study, potassium counteracts stiff arteries and atherosclerosis by inhibiting the uptake of calcium in the smooth muscle cells of arteries. Other studies suggest that cholesterol (which is essential to humans) does not become a cardiovascular threat, unless it is attacked by free radicals that oxidize it and makes it stick to the arterial walls and cause inflammation.

References:

Dietary potassium may protect against calcification of arteries
http://www.nutritioninsight.com/news/dietary-potassium-may-protect-against-calcification-of-arteries.html

https://www.sundhedsguiden.dk/da/temaer/alle-temaer/hjerte-kar-sygdomme/almindelige-hjerte-kar-sygdomme/aareforkalkning-arteriosklerose-og-aterosklerose/

http://frida.fooddata.dk/QueryFood.php?fn=avokado

Harlan Krumholz. Inflammation: Is it the New Cholesterol? Pharma & Healthcare medicine. August 2017
https://www.forbes.com/sites/harlankrumholz/2017/08/27/inflammation-is-it-the-new-cholesterol/#1aa491905b05