Potassium: The Electrolyte Most People Overlook

Potassium is the mineral nobody markets. It has three authorised health claims, a well-documented intake shortfall in the UK, and almost no presence in the wellness conversation. It also has genuine safety considerations, which is probably part of why.

What Potassium Does

Potassium is the main positively charged ion inside your cells, and it works in partnership with sodium to maintain the electrical gradients that let nerves fire and muscles contract. Your heart is a muscle, which is why potassium balance is tightly regulated by the kidneys and why it matters clinically.

The Three Authorised Claims

Potassium carries three authorised health claims on the GB Nutrition and Health Claims Register:

• Potassium contributes to the normal functioning of the nervous system.
• Potassium contributes to normal muscle function.
• Potassium contributes to the maintenance of normal blood pressure.

That third claim is unusual. Very few supplement ingredients carry an authorised claim relating to blood pressure, and potassium's position reflects a substantial body of evidence on the sodium–potassium relationship.

The UK Intake Picture

National Diet and Nutrition Survey data has consistently shown a proportion of UK adults consuming less potassium than the Reference Nutrient Intake, with the shortfall more common among women and younger adults. The reasons are unsurprising: potassium is concentrated in vegetables, fruit, pulses, potatoes, fish and dairy, and UK diets tend to be lighter on those than dietary guidance would like.

Meanwhile sodium intake runs high. It is the ratio between the two, rather than either in isolation, that much of the blood-pressure literature concerns itself with.

Food First — Genuinely

I say this about most minerals, but it applies with particular force to potassium. Food sources deliver it alongside fibre, magnesium and a great deal else, and the amounts are substantial: a baked potato with skin, a portion of white beans, spinach, salmon, or a banana all contribute meaningfully.

Supplemental potassium in the UK is deliberately limited to modest per-capsule amounts precisely because the food route is both safer and more effective at scale. Our Potassium Citrate provides 300mg per capsule — a contribution to daily intake, not a replacement for eating well.

The Safety Part, Which Is Not Optional Reading

Potassium is one of the few supplements where I would ask you to stop and check rather than simply try it. Excess potassium is cleared by the kidneys, and where that clearance is impaired it can accumulate to genuinely dangerous levels.

Speak to your GP before taking supplemental potassium if you:

• have any degree of reduced kidney function
• take ACE inhibitors, angiotensin receptor blockers, or potassium-sparing diuretics such as spironolactone or amiloride
• take NSAIDs regularly
• have diabetes, adrenal insufficiency, or a heart condition
• use potassium-based salt substitutes such as LoSalt

That last one catches people out. Potassium-based salt substitutes contribute a meaningful amount, and combining them with a supplement while on a potassium-sparing medication is exactly the scenario to avoid.

Why Citrate

We use potassium citrate — potassium bound to citric acid — because it is well tolerated and widely used in supplementation. Some other forms are more irritating to the gastrointestinal tract.

The Short Version

Potassium is genuinely under-consumed in the UK and genuinely useful, with three authorised claims including one on blood pressure. It also has a narrower safety margin than most minerals. Eat more plants first; if you supplement, check your medications before you do.