Potassium, the Rarely Mentioned Friend of Blood Pressure
The blood pressure story usually revolves around salt alone. But there is another mineral working in the opposite direction, and many people are eating too little of it.
But · 4 min read · Sep 5, 2026
When blood pressure comes up, people tend to think straight away of salt. But the body keeps blood pressure steady through a balance between two minerals: sodium in salt and potassium in fresh food. When the scales tip too far towards sodium, blood pressure tends to rise.
Two minerals, two directions
Sodium holds water inside the blood vessels. More water means a larger blood volume, and higher pressure on the vessel walls.
Potassium does the opposite. It helps the kidneys pass out some of the sodium and helps the vessel walls widen more easily. So what deserves your attention is not only how much salt you eat, but the ratio between the two in your daily meals.
Modern meals tend to be heavy on processed food and light on fresh vegetables, so the scales tip easily: plenty of sodium, little potassium.
Where potassium is plentiful
- Bananas, papaya, oranges, avocado, watermelon
- Sweet potato, potato, pumpkin
- Dark leafy greens: water spinach, spinach, amaranth
- Beans and pulses, black beans, mung beans, soya beans
- Fish, unsweetened yoghurt, nuts and seeds
What this group has in common is that they are fresh foods, little processed. Eating a variety of vegetables and fruit every day is the most natural way to get enough potassium, rather than reaching for a supplement.
A few notes on cooking
Potassium dissolves in water, so vegetables boiled at length with the water poured away lose some of it. Steaming, a quick stir-fry, or using the soup broth as well keeps more of it.
The low-salt substitutes sold on the market usually replace part of the sodium with potassium. They are useful for some people but risky for those with kidney disease, so do not switch to them on your own without asking your doctor.
When to see a doctor
See a doctor if your blood pressure is regularly 140/90 mmHg or above despite adjusting what you eat, or if you have kidney disease or diabetes and want to know the potassium level that suits you.
Go to a medical facility immediately if you notice marked muscle weakness, numbness, an irregular heartbeat or unusual palpitations, especially if you are taking diuretics or blood pressure medication.
This information is for general reference only and does not replace advice from your doctor.
