What is potassium?
Potassium is an essential mineral that has several roles in the body, including: regulating muscle contractions, maintaining healthy nerve function and regulating fluid balance. Also, potassium is present in all of the body's cells and tissues.
There are several health benefits associated with potassium, but today I am going to focus on how it can:
- Help to reduce blood pressure
- Reduce the risk of stroke
- Help to prevent kidney stones
- Enhance bone mineral density.
1. Helping to reduce blood pressure
Hypertension is defined as a blood pressure reading of 140/90 mmHG or higher.1 Consuming excessive amounts of salt can contribute towards hypertension. Consuming too much salt causes your kidneys to hold on to more water. This extra water puts more strain onto your kidneys and arteries, ultimately contributing to high blood pressure.
Potassium helps to lower blood pressure by balancing out the negative effects of salt. As well as this, potassium relaxes the walls of the blood vessels which can lower blood pressure. Extensive research has shown that a higher intake of potassium can help to reduce blood pressure. One study, for example, found that daily intake of potassium significantly reduced systolic and diastolic blood pressure.2
Furthermore, high blood pressure is one of the main risk factors for cardiovascular disease (CVD). Research has shown that increased consumption of fruit and vegetables was associated with a lower risk of CVD.3 Potassium is found in a range of fruit and vegetables including: bananas, grapefruit, potatoes, tomato juice and mushrooms. So, adding some potassium-rich foods into your diet could help to keep your heart healthy.
2. Reducing the risk of stroke
CVD is the name for a group of disorders of the heart and blood vessels, which include hypertension, coronary heart disease and stroke. According to the World Health Organisation an estimated 17.9 million people died from CVD in 2016 and of these deaths, 85% were due to stroke and coronary heart disease.4
Stroke and high blood pressure go hand in hand since high blood pressure is one of the main risk factors for stroke. High blood pressure can damage the blood vessels, making them stiffer. This type of damage can lead to the formation of blood clots which stop blood supply to the brain. This is called an ischaemic stroke and is the most common types of stroke.
Since potassium can help to relax the blood vessels, this is thought to be one reason it can help to reduce the risk of a stroke. One review, in particular, found that intake of dietary potassium helped to reduce the risk of stroke and cardiovascular disease.5
3. Helping to prevent kidney stones
Kidney stones are quite common in people aged between 30 and 60 and they can be extremely painful! These can become a serious issue and can lead to the kidneys not working properly if left untreated.
Kidney stones are usually formed as certain chemicals build up in the body. Stones containing calcium in the form of calcium oxalate or calcium phosphate are the most common type of kidney stone.
Diets that are low in potassium have also been linked to an increased risk of kidney stones. One study found that higher dietary potassium was significantly associated with less risk of kidney stones.6
4. Enhanced bone mineral density
Nutrition is a major factor that can affect bone health. Bone mineral density is the amount of bone mineral that is present in your bones. A bone mineral density test can be conducted to measure the quantity of minerals (mainly calcium and phosphorus) in your bones. A bone density test is the only test that can diagnose osteoporosis.
Research has found that consuming sufficient potassium through diet had a positive effect on bone mineral density in both men over 50 and postmenopausal women.7 This is another good reason to keep your intake up!
In addition, one of potassium's main roles is muscle contraction, which helps to keep the skeletal muscles working effectively. Potassium deficiency can therefore reduce the effectiveness of various muscles in the body and it can contribute towards muscle weakness and muscle cramps. These can be very painful and tend to occur in the leg and foot muscles. Research has found that low potassium intake is associated with muscle cramps. For example, one study found that women with painful muscle cramps had lower intakes of potassium in their diet.8
How much potassium do we need?
Below, I have included a handy table to help you identify how much potassium you need each day based on the recommendations from the British Nutrition Foundation.9
Too much potassium
Whilst potassium is an essential nutrient for health, consuming too much potassium can be dangerous and can seriously impact your health. Normally, if too much potassium is consumed, your kidneys filter it out and it is excreted in the urine, stool or sweat. However, if your kidneys are not as effective at filtering, the excess levels of potassium build up to a harmful level. Too much potassium is called hyperkalemia.
Common symptoms of hyperkalemia include abdominal cramps, muscle weakness and nausea. If left untreated it could lead to heart problems. Therefore, you should not take potassium supplements without medical advice from your doctor if you have kidney problems. If you are concerned about your potassium levels do not hesitate to see your doctor.
Which foods contain potassium?
Potassium is found naturally in a wide range of foods and is easily absorbed by the body. Below, I have included a handy table to help you identify which foods contain potassium.
||Amount of potassium (mg)
|Dried apricots, 100g
|1 sweet potato
|1 medium sized banana
|Cooked lentils, 100g
|Cooked broccoli, 100g
|1 large tomato
What can you take away from this blog?
- Potassium is an essential mineral that is associated with several health benefits, including: helping to reduce blood pressure, reducing the risk of stroke, helping to prevent kidney stones and enhancing bone mineral density.
- Everyone over the age of 15 in the UK needs 3500mg of potassium daily.
- Potassium is found in a wide range of foods and can easily be included into your diet.
- If you are concerned about your potassium levels you should speak to your doctor.
What you said!
We recently ran a poll to find out if you will include more foods that contain potassium in your diet. We've crunched the numbers and here are the results.
Results: Will you include more foods that contain potassium in your diet?
It's great to see that 94% of you will include more foods that contain potassium in your diet. Potassium has many important roles within the body and, so, is a vital part of the diet.