The best potassium supplement

Ana Sanchez

Be aware that some low-sodium foods and multivitamins contain added potassium. These shouldn’t be ingested in addition to a potassium supplement.

Though a potassium deficiency is not common, some conditions can lead your potassium levels to drop, and you may experience muscle spasms, high blood pressure, and nervous system dysfunction. We all need potassium in our bodies to regulate our metabolism, and the mineral also plays a part in digestion. It's best to check with your doctor before starting potassium supplements, as too much can be dangerously toxic to the body.

If it's been recommended for you to supplement with this mineral, read our quick guide for all you need to know when purchasing a potassium supplement. We've included information about our top brands, including our favorite potassium supplement by Nature Made that contains an elemental form of the mineral that's easy for the body to absorb.

Signs and causes of potassium deficiency

Most people get enough potassium from their food. Bananas, avocados, beans, and sweet potatoes are a just a few examples of potassium-rich foods. However, some people, such as high-endurance athletes, are at risk for potassium deficiency. Here are some of the signs of a mild deficiency:

Muscle cramps and spasms
Fatigue and weakness
High blood pressure
Trouble concentrating
Heart palpitations (in more severe cases)

Of course, these are common signs of other ailments, so never self-diagnose without first checking with a qualified healthcare practitioner. There are many conditions that could cause a potassium deficiency, including kidney malfunction, dehydration, antibiotic use, hyperthyroidism, alcoholism, diabetes, and excessive laxative use.

Considerations when choosing potassium supplements


There are many forms of potassium available in supplements: potassium gluconate, aspartate, chelate, chloride, phosphate, bicarbonate, citrate, and orotate. Potassium chloride is the most common type used to treat deficiency.


The recommended daily intake (RDI) for potassium is 4,700 mg. Most supplements come in 90 mg to 99 mg doses of potassium. Higher-dose pills are available, but they usually contain smaller "active" amounts. For your frame of reference, a banana contains 487 mg of potassium.


Potassium supplements come in capsule and tablet form. Liquids and powders are also available, though less commonly so. In severe cases, potassium can be injected by a doctor. For capsules and pills, there are plenty of vegetarian options as well as formulas free from dairy, gluten, wheat, GMOs, and other common allergens.


Some supplements can be expensive. Fortunately, potassium supplements tends to run on the inexpensive side. They are priced from .02 to .25 per pill. Mid-range potassium supplements that are priced from .10 to .15 per pill may contain different types of potassium as well as higher dosages per pill. Premium potassium supplements, costing up to .25 per pill, are typically marketed as part of an electrolyte package targeting athletes.


Q. Should I take a potassium supplement with food?

A. Yes. Potassium supplements can cause stomach discomfort, such as nausea, which is mitigated for most consumers when taken with food and plenty of water or another beverage.

Q. Who shouldn't take potassium supplements?

A. Always check with your doctor before taking potassium supplements, especially if you're taking blood pressure drugs or have heart or kidney problems. Potassium supplements can also interact with a number of medications.

Q. Can you overdose on potassium supplements?

A. Ingesting too much potassium can lead to a dangerous condition called hyperkalemia, when there is a buildup of potassium in the blood. These can cause heart arrhythmia (irregular heartbeat), which can cause serious problems.

Potassium supplements we recommend

Best of the best: Nature Made Potassium Gluconate Tablets

Our take: From a trusted brand for quality, a highly absorbable form of potassium

What we like: Each tablet contains 90 mg of elemental potassium. No artificial flavors, colors, or preservatives. USP-certified for purity.

What we dislike: Tablet form can be chalky.

Best bang for your buck: NOW Foods Potassium Citrate

Our take: A highly absorbable form of potassium at a easy-to-stomach price.

What we like: Vegetarian gel capsules. Delivers fast results, especially if you suffer from leg cramps.

What we dislike: May cause upset stomach.

Choice 3: Pure Encapsulations Potassium Citrate Supplement  

Our take: A brand known for its stringent standards, a very pure form of potassium.

What we like: Capsules are small. Hypoallergenic and free of unnecessary fillers, including artificial colors and flavors.

What we dislike: On the expensive side.

Ana Sanchez is a writer for BestReviews. BestReviews is a product review company with a singular mission: to help simplify your purchasing decisions and save you time and money. BestReviews never accepts free products from manufacturers and purchases every product it reviews with its own funds.

BestReviews spends thousands of hours researching, analyzing and testing products to recommend the best picks for most consumers. BestReviews and its newspaper partners may earn a commission if you purchase a product through one of our links.

Distributed by Tribune Content Agency, LLC.