Onions are a globally popular vegetable that’s easy to incorporate into many dishes, adding their distinctive flavor to soups, sauces, and salads. Onions are almost ubiquitous, with 175 countries producing a crop, over twice the number that grow wheat. They’re highly nutritious and a staple of every major cuisine.

However, many people now follow diets that aim to increase or decrease their intake of certain nutrients, such as the low-potassium diet followed by kidney disease sufferers. People on such a diet must know the potassium content of common foods before including them in their meals and stay within the daily intake recommended by their doctor.
How well do onions fit into the meal plans of these people?
Table of Contents
Are Onions High or Low in Potassium?
Onions are low in potassium and are safe for those on a low-potassium diet. They’re also highly nutritious and contain many beneficial compounds and antioxidants.
How Much Potassium Is in Onions?
One medium raw onion contains 161 mg of potassium, below the 200 mg per serving threshold for low-potassium foods. A medium-cooked onion contains around 156 mg.
Most onion varieties contain similar amounts.

Are Onions Healthy?
Onions are high in vitamin C, which supports immune system regulation, collagen production, tissue repair, and iron absorption. It's also a powerful antioxidant, helping flush out harmful free radicals and preventing oxidative stress and cellular damage that can lead to diabetes and cancer.
Onions contain potent antioxidants and compounds that reduce cholesterol levels and fight inflammation, lowering the risk of cardiovascular disease.
These compounds also help reduce blood pressure, lowering your stroke risk.
Onions, especially red, also contain compounds that reduce your blood sugar levels, helping prevent and manage the symptoms of diabetes.
Can You Get Too Much Potassium from Onions?
It would be almost impossible to get too much potassium purely by eating onions.
Is Onion Soup High in Potassium?
One cup of canned onion soup contains 68 mg of potassium, and a cup prepared using a dry mix contains 71.3 mg. One cup of canned cream of onion contains around 120 mg, as the heavy cream used in its manufacture adds potassium and calories.
Store-bought soups often contain a lot of sodium, which can lead to high blood pressure.
Are Spring Onions High in Potassium?

One cup of chopped spring onions contains around 276 mg of potassium, much higher than regular onions.
However, spring onions are high in vitamins A, C, and K, folate, calcium, iron, and manganese.
Are Onion Flakes High in Potassium?
Like most dried foods, onion flakes are quite high in potassium, with a quarter cup containing 227 mg.
Are Onion Rings High in Potassium?
Ten medium-sized onion rings contain around 77.4 mg of potassium.
However, they're high in fat and processed foods are associated with an increased risk heart attack, stroke, and cancer.
Conclusion
Onions are highly nutritious and safe for most people on a low-potassium diet. However, if you follow such a diet, remember to record your daily intake and stay within the limit set by your doctor.
Don't know which foods are high in potassium? Read our article, 15 Best Food Sources of Potassium. We also have a guide to this important mineral: Potassium 101: All You Need To Know About Potassium.