💊 What it does
Potassium is the primary intracellular electrolyte, essential for nerve signalling, muscle contraction, heart rhythm, blood pressure regulation, and fluid balance. Adequate potassium intake is one of the most important dietary factors for blood pressure management — it counters the effects of sodium and relaxes blood vessel walls. The UK recommended intake is 3,500 mg/day, but average intake is significantly below this. A diet rich in fruits, vegetables, and legumes naturally provides high potassium.
👤 Who needs it
People with hypertension — adequate potassium intake is a cornerstone of dietary blood pressure management. Athletes with high sweat losses. Those with low fruit and vegetable intake. People on diuretic medications that deplete potassium (loop diuretics like furosemide). Note: supplementation is rarely needed for people eating adequate plant foods.
🥦 Food sources first
Potassium is exceptionally abundant in plant foods: bananas, avocados, sweet potatoes, potatoes (especially with skin), spinach, kale, white beans, lentils, chickpeas, tomatoes, beetroot, oranges. A plant-rich diet typically provides far more potassium than a typical Western diet. This is one nutrient where food is almost always superior to supplements.
🗓 When to supplement
Only when dietary intake is genuinely insufficient AND medical supervision confirms it is safe. UK supplement regulations limit potassium to 200 mg per tablet — far less than the daily target, reflecting appropriate caution. Food should always be the primary potassium source.
🏷 Best form to look for
Potassium citrate or potassium gluconate are well-absorbed forms. Potassium chloride (salt substitute, e.g. LoSalt) is an accessible dietary source that provides meaningful potassium.
⏰ When to take it
With food — potassium on an empty stomach can cause GI upset. Spread throughout the day rather than one large dose.