Potassium: Why You Need It and How to Get Enough From Food

What potassium actually does in the body, why most people fall short of it, and which everyday foods — including moringa — are good sources.

Potassium is an essential mineral. Along with its role in fluid balance, it contributes to normal muscle function, to the normal functioning of the nervous system, and to the maintenance of blood pressure that's already within a normal range. Most people don't think about it until they hear the word, but it is one of the nutrients a lot of adults simply don't get enough of.

A study examined potassium intake in the USA by collecting data from about 29,000 men and 30,000 women between ages 12 and 80 years old. The results showed an apparent decline in serum potassium across the US population from 1999 to 2016. Separately, an analysis of national dietary data suggests 98% of American diets fall short of the recommended amount, largely because they don't include enough plants.

Why intake tends to run low

The main driver is straightforward: a diet heavy in processed food is naturally heavy in sodium and light in potassium, and the two minerals work as a pair — the more sodium you eat, the more potassium your body excretes. For most people, getting enough comes down to eating more of the foods further down this page, consistently, rather than any single fix.

Low potassium can also have causes beyond diet — including certain medications, prolonged vomiting or diarrhoea, or an underlying kidney or hormonal condition. Those causes need a diagnosis rather than a grocery list, so if you suspect something beyond diet is going on, that's a conversation for a doctor.

Why the body needs it

Potassium plays a genuine, well-established role in several everyday systems:

Muscle function — potassium is involved in every muscle contraction in the body, including your heartbeat.
Nerve function — nerve signals depend on potassium moving in and out of cells.
Fluid balance — potassium works opposite sodium to help regulate the fluid inside and outside your cells.
Blood pressure — potassium is one of the nutrients most studied in relation to blood pressure, and most adults take in less of it than dietary guidelines suggest.

A sustained shortfall can show up as general tiredness, muscle cramping, or a change in bowel regularity, since the same signalling potassium provides to skeletal muscle also drives the muscle that moves food through your gut. None of that is a diagnosis on its own — those symptoms have plenty of other causes too, so if something like this doesn't resolve, it's worth getting checked rather than guessed at.

Potassium-rich foods

For most people, the straightforward move is eating more of these:

Beans, lentils
Bananas
Potatoes
Avocado
Leafy greens like moringa
Cashews
Chicken
Salmon
Yogurt
Oranges
Coconut water
Tomatoes

Moringa is a useful one to know about: it's a leafy green that's a source of potassium. A teaspoon or two of moringa powder stirred into a smoothie or soup is a simple way to add some, alongside the rest of the list above.

If you suspect an actual potassium deficiency, the reliable way to know is a blood test, not a symptom list. A healthcare professional is the right person to confirm it and, if needed, work out the cause.

These statements have not been evaluated by the Food and Drug Administration. These products are not intended to diagnose, treat, cure, or prevent any disease.