High potassium: recognising the symptoms and maintaining balanced levels

Potassium is a mineral found in significant quantities in our bodies. It is one of the most abundant minerals within our cells, which store around 98 per cent of it, with the remaining 2 per cent circulating in the blood. Our bodies cannot produce it, so it must be obtained from our diet. Potassium is an electrolyte, that is to say, a mineral that becomes ionised in the presence of liquid. These ions are necessary for electrical conduction, which enables nerves and muscles to function properly. Potassium therefore plays a role in muscle contractions, the functioning of the cardiovascular system and acid-base balance. A normal blood potassium level is between 3.5 and 5.0 mEq/L. Above this, it is considered too high, a condition referred to as hyperkalaemia. It is considered mild up to 6.0 mEq/L and is deemed severe above 6.5 mEq/L.

Excessive intake: a high consumption of potassium-rich foods rarely accounts for hyperkalaemia on its own; it is often exacerbated by taking dietary supplements in excessive quantities or at high doses. Injections of potassium-rich solutions can also be a cause. It should be noted, however, that in the majority of healthy people, even excessive intake generally has no adverse effects, particularly if the kidneys are functioning properly. 

Impaired excretion: the kidneys excrete minerals via the urine. Kidney failure may explain an excessive presence of potassium in the body. This may also be caused by taking certain medicines, such as non-steroidal anti-inflammatory drugs or certain diuretics, which can limit its natural excretion and thus promote its accumulation in the body.

Potassium shift: potassium can sometimes move from the intracellular to the extracellular environment. This can occur in very specific circumstances, for example following a burn, cell necrosis, in the case of insulin deficiency or in the presence of metabolic acidosis.

Hyperkalaemia (high potassium levels) is usually asymptomatic at first, but can then lead to several symptoms when levels exceed 6 mmol/L:

• General weakness: tiredness, feeling unwell, or even confusion in severe cases

• Digestive problems: abdominal pain, diarrhoea, nausea and vomiting may occur

• Muscle weakness: loss of strength, which may lead to progressive paralysis

• Cardiac arrhythmia: irregular heartbeat, palpitations

• Serious cardiovascular risks: at levels above 7 mmol/L, hyperkalaemia can cause ventricular fibrillation or cardiac arrest, requiring urgent medical attention.

If a blood test reveals that your potassium levels are too high alongside your symptoms, the first step is always to consult a doctor promptly. Hyperkalaemia can have serious consequences and requires appropriate treatment. Depending on the severity and cause, different medical options are available:

Adjusting or discontinuing certain medicines (diuretics, anti-inflammatories, high blood pressure treatments) that may contribute to hyperkalaemia.

Following a specific diet, often with the support of a dietitian, to reduce potassium intake without causing a deficiency.

Administering emergency treatment if levels are very high (ion-exchange resins, calcium infusions, insulin combined with glucose, etc.), always under medical supervision.

Monitoring kidney function: regular monitoring of blood tests and glomerular filtration rate helps to track changes in potassium levels.

Self-medication is not recommended: only a healthcare professional can decide on the appropriate course of action for your situation.

This advice is aimed in particular at people considered to be at risk, such as those suffering from kidney failure:

1. Drink enough water: (unless medically restricted) to help the kidneys eliminate potassium

2. Avoid excessive supplementation: taking dietary supplements is not without risk and should only be done to meet a genuine need. Taking supplements without having a proven deficiency is pointless and can sometimes lead to side effects, such as an excess of certain minerals or vitamins

3. Do not overconsume foods rich in potassium: certain fruits and vegetables are rich in potassium, such as bananas, kiwis, avocados, dried fruit and nuts, potatoes and green leafy vegetables, amongst others. People at risk are advised to be mindful of their food choices in order to limit these foods and favour those with a lower potassium content, such as apples, grapes, green beans, carrots and aubergines. 

4. Adopt certain methods for cooking vegetables: cooking vegetables in a large quantity of water and then discarding this water helps to reduce their potassium content. Avoid reusing the cooking water for soups or stocks.

The advice given in this article on relieving the symptoms of high potassium levels is in no way a substitute for medical supervision, which is essential in cases of hyperkalaemia, as this condition can lead to serious complications. The various symptoms mentioned in this article may have other causes; only a medical consultation and appropriate tests can establish an accurate diagnosis. 

People with excessively high potassium levels need to be careful about the foods they choose when planning their meals. Fresh, dried and nut fruits, as well as vegetables, contain potassium in varying amounts; however, completely eliminating them from the diet is not advisable, as they are rich in nutrients and fibre, which is essential for our health. Guidance from a nutritionist helps you maintain a healthy, balanced diet and avoid nutritional deficiencies by selecting the foods best suited to your specific needs. 

After completing a Master's degree in Management, Christine spent around twenty years working for renowned companies in the food supplement and natural cosmetics sectors, then decided to turn their passion for nature into a profession. They now practise naturopathy for both people and animals, as well as sophrology, and mentor trainee naturopaths and sophrologists at various schools.