Nutrient glossary
What is potassium?
Potassium is the counterweight to sodium: it relaxes blood vessels, supports nerves and muscles, and most people fall short.
Reviewed 20 July 2026. General information, not medical advice.
The short version
Potassium sits inside your cells doing the opposite job to sodium, and blood pressure tracks the balance between the two. Diets rich in potassium from plants are consistently linked with lower blood pressure and stroke risk, yet average intakes sit well under the reference.
It is everywhere in whole food: potatoes, beans, yogurt, fish, bananas, greens. It mostly goes missing when meals shift to processed food, which swaps potassium out and sodium in.
Daily reference
3,500 mg a day
The adult reference is 3,500 mg a day.
This is the fixed adult reference used across these pages. In the app, your amount adjusts to your body and way of eating.
Best food sources of potassium
Full ranking| Food | Per serving | Per 100g |
|---|---|---|
| Potato (baked) | 926 mg | 535 mg |
| Halibut | 739 mg | 528 mg |
| Lentils (cooked) | 731 mg | 369 mg |
| Cannellini Beans | 729 mg | 561 mg |
| Tuna Steak | 685 mg | 527 mg |
| Butter Beans | 660 mg | 508 mg |
| Coconut Water | 625 mg | 250 mg |
| Black Beans (cooked) | 611 mg | 355 mg |
Common questions
- What food has the most potassium?
- Per serving, a jacket potato is hard to beat at around 900 mg. Beans, yogurt, fish and bananas all contribute meaningfully.
- Can you have too much potassium?
- From food it is very hard with healthy kidneys. High-dose supplements are a different matter and belong under medical advice.