Low potassium levels, or hypokalemia, can lead to muscle cramping, weakness, fatigue, and other symptoms. Potassium supplements may help, although they cannot treat underlying causes of hypokalemia.
A quick look at the best potassium supplements
- Best vegan potassium capsule: NOW Supplements Potassium Citrate 99 mg
- Best for a high serving volume: Nutricost Potassium Citrate 99 mg
- Best for potassium gluconate: CVS Health Potassium Gluconate 650 mg Caplets
- Best liquid potassium: Trace Minerals Liquid Ionic Potassium
This article will discuss the role of potassium within the body and mention some reasons a person may need to take a potassium supplement.
It will also provide information on dosages and possible side effects, and list four of the best potassium supplements available.
What is dietary potassium?
Dietary potassium refers to potassium that comes from foods. Many plant and animal foods contain potassium. Some examples include:
- fruits, including dried fruits
- nuts
- legumes
- brown rice
- whole wheat flour
- milk
- yogurt
- meat
The body absorbs about 85–90%Trusted Source of dietary potassium.
What does potassium do?
Potassium plays a major role in maintaining the water content of cells. It is also essentialTrusted Source for:
- nerve transmission
- muscle contractions
- proper kidney function
Most of the potassium in the body is stored inside cells. Typical potassium concentrations in the blood range from around 3.6 to 5 millimoles per literTrusted Source.
Blood potassium levels can indicate potassium status, but they cannot indicate what the stores are like inside the cells.
Why might people need potassium?
In people with regular kidney function, abnormally low or high potassium levels in the blood are rare.
However, certain factors can decrease potassium levels. Some examples include:
- diarrhea
- vomiting
- heavy sweating
- eating following a period of starvation
- overconsuming laxatives
- overusing diuretics
- dialysis
- magnesium depletion
- following a keto diet
- eating clay (a type of pica)
People with any of the above risk factors may benefit from taking a potassium supplement.
Potassium supplements and the keto diet
Keto diets are high fat, low carbohydrate, moderate protein diets. Some people follow a keto diet to assist with weight loss.
A keto diet may also help people with the following conditionsTrusted Source, although there is not enough research to support its use in all these cases:
- diabetes and other metabolic disorders
- epilepsy
- dementia
- amyotrophic lateral sclerosis
- traumatic brain injury
- acne
- some aggressive metastatic cancers
However, it may involve some risks.
The keto diet increases the acidic environment of the body. This can trigger metabolic acidosis (MA), in which the blood becomes too acidic. This can lead to kidney problems and a loss of bone mineral density.
One 2020 studyTrusted Source suggests that oral potassium citrate supplementation may prevent the risk of MA in children following a keto diet. The researchers suggest potassium citrate acts as an alkalizing agent to counteract the potential for MA.
Further studies are necessary to determine whether everyone following a keto diet should take a potassium citrate supplement.
It is also important to note that experiencing MA due to following a keto diet is extremely rareTrusted Source in people without a preexisting health condition.
Dosage
Most dietary supplements contain potassium salts. Potassium salt is a combination of potassium and one or more other elements.
Dietary potassium supplements typically containTrusted Source potassium chloride. However, some contain other potassium salts, such as:
- potassium citrate
- potassium phosphate
- potassium aspartate
- potassium bicarbonate
- potassium gluconate
Since these different salts contain different amounts of potassium, the supplement label may show the amount of pure, or elemental, potassium in the product.
Multivitamins and mineral supplements that contain potassium typically contain about 80 milligrams (mg)Trusted Source of elemental potassium. Potassium-only supplements often contain up to 99 mg of elemental potassium.
Different supplements contain different amounts of potassium, so people should read the individual product labels to determine the appropriate dosages.
How we chose
Medical News Today chooses products that meet the following criteria:
- Ingredients: MNT chooses products containing safe and high quality ingredients that are clearly labeled. They should also confirm they are free from pesticides, heavy metals, and mold.
- Dosage: MNT chooses products that must clearly state the supplement dosage.
- Serving size: MNT selects products in which manufacturers recommend a safe dosage.
- Third-party testing: MNT chooses products that must undergo third-party testing for contaminants by an ISO 17025-compliant laboratory.
- Available certificate of analysis: MNT chooses companies that demonstrate transparency and share a product’s certificate of analysis (COA) after receiving its third-party lab results.
List of the best potassium supplements
The National Institutes of Health identify hundreds of dietary supplements that contain potassium. The sections below outline four potassium supplements suitable for different uses and preferences.
Please note that the writer of this article has not tried these products. All information presented is purely research-based and correct at the time of publication.
Medical News Today follows a strict product selection and vetting process. Learn more here.
Best vegan potassium capsule: NOW Supplements Potassium Citrate 99 mg
- Price: around $13
- Type: capsule
- Dose: 99 mg
- Servings: 180
NOW Supplements claims this supplement is vegan and soy-, nut-, and gluten-free.
The label suggests it helps support electrolyte balance, pH, and proper muscle contractions. It states that potassium citrate is a highly bioavailable form of potassium.
The dosage information states that a person should take 1 capsule one to five times daily with food.
If a person takes this supplement five times per day, they will get 10% of the recommended daily intake of potassium. However, a person should start slowly with new supplements and on the lowest dosage to be sure they tolerate it well.
The company claims this supplement is made in a Current Good Manufacturing Practice (CGMP)Trusted Source certified facility. This means that the entire manufacturing process has been examined, and the product has been tested for stability, potency, and the accuracy of its ingredients.
Positive reviews show that this product is a good price for the serving volume and the supplements effectively reduced leg cramps.
However, some buyers wrote that there were unmarked tablets and empty capsules in the container, and others did not like taking up to five capsules a day.
Best for a high serving volume: Nutricost Potassium Citrate 99 mg
- Price: around $18
- Type: capsule
- Dose: 99 mg
- Servings: 500
Nutricost Potassium Citrate 99 mg is a non-genetically modified organism and gluten-free supplement.
The manufacturers recommend taking 1 capsule with eight to 12 ounces of water, or as a doctor suggests.
There are 500 capsules in each bottle, making this product suitable for people who know they need to take potassium supplements long-term.
Positive reviews for this Nutricost potassium supplement write that it helped boost energy and reduce leg cramps, and the serving volume lasted buyers a long time.
However, some buyers are critical of the rice flour filler in the capsules, and others state it does not contain enough potassium.
Best for potassium gluconate: CVS Health Potassium Gluconate 650 mg
- Price: around $6
- Type: caplets
- Dose: 99 mg
- Servings: 100
These supplements use potassium from potassium gluconate. They include potassium and gluconic acid. This type of potassium supplement is specifically used to treat low potassium levels.
CVS Health writes these supplements may support muscle and nerve health and may regulate neuromuscular activity.
Each caplet contains 99 mg of potassium from 650 mg of potassium gluconate, providing 2% of a person’s recommended daily intake. The company recommends a person takes one caplet a day.
It states the caplets are vegan and gluten-free and do not contain soy, artificial colors, flavors, or preservatives.
There are limited written reviews for this product online, but many buyers rate it 5 out of 5 stars on the CVS website. However, some critical reviews state the caplets were too large to swallow comfortably, and others felt misled by the product packaging regarding the potassium content of the caplets.
Best liquid potassium: Trace Minerals Liquid Ionic Potassium Supplement
- Price: around $13
- Type: liquid
- Dose: 99 mg
- Servings: 33
This potassium supplement is an option for people who find capsules and tablets difficult to swallow. Each 1/3 teaspoon serving provides 99 mg of potassium and a range of other minerals. This includes 30 mg of magnesium, 300 mg of chloride, and 65 mg of sodium.
Trace Minerals writes that the ionic potassium in this supplement is a concentrated liquid form that can help support muscle, nerve function, and heart and brain health.
A person can measure each serving with the metered dropper. Although this means a person can measure their dose, it may be less accurate than taking a tablet or capsule. Trace Minerals suggests a person adds these drops to drinks or food.
The company claims this product is third-party tested, Non-GMO Project verified, and made in a CGMP-certified facility.
Positive reviews mention that this supplement helped to ease leg cramps and was easy to take. Negative reviews frequently mention its unpleasant taste. Others felt it did not contain enough potassium as it provides 2% of a person’s recommended daily intake.
Comparison
The table below compares each potassium supplement in this article for dose, price, ingredients, and servings.
| NOW Supplements | Nutricost | CVS Health | Trace Minerals | |
|---|---|---|---|---|
| Type | capsules | capsules | caplets | liquid |
| Dose | 99 mg | 99 mg | 99 mg | 99 mg |
| Potassium form | potassium citrate | potassium citrate | potassium gluconate | potassium chloride |
| Ingredients | potassium | potassium | potassium | • magnesium • chloride • sodium • potassium • sulfate • trace minerals |
| Servings | 180 | 500 | 100 | 33 |
| Price | around $13 | around $18 | around $6 | around $13 |
How to use
Before taking a potassium supplement, a person should speak with a doctor. Most cases of hypokalemia are not solely due to a lack of potassium intake, so it is important to identify and treat the underlying cause of the hypokalemia.
If a person is considering taking a potassium supplement, they should ask a doctor or pharmacist for advice on dosage. They should also follow any instructions on the package or from the doctor or pharmacist.
For more in-depth resources about vitamins, minerals, and supplements, visit our dedicated hub.
How to choose
- Ingredients: A person should carefully read the ingredients list of their chosen supplement. They should avoid products that do not list their ingredients. Additionally, not all supplements are suitable for people following different diets. Some capsules and gummies contain gelatin and will not be suitable for vegan or vegetarian diets.
- Dose: A person should check the dose each serving will provide them. Buyers should not exceed the recommended daily value of any vitamin, mineral, or other nutrients, as it can be dangerous. People should avoid products that do not state the dose and do not recommend a dosage.
- Type: People may prefer to take supplements in different forms, such as capsules, gummies, or liquids. Gummies and liquids are a good alternative for people who cannot or do not like to swallow capsules or tablets. However, the dose of a liquid supplement may be harder to measure.
- Testing: Buyers should choose products that have third-party testing assurance. This means that an independent laboratory has tested the product to make sure it contains the ingredients it lists on the packaging, is free from contaminants and harmful substances, and contains the correct dose.
- Health claims: A person should avoid products from manufacturers that make unsupported health claims. Supplements cannot cure serious conditions, and a person should research the effectiveness of their chosen supplement for its intended use before making a purchase.
- Price: Some supplements can be expensive. A person should consider how long the serving volume will last and how cost-effective the supplement will be if a person takes it long-term.
Side effects
Potassium supplements can sometimes cause minor digestive side effectsTrusted Source.
High doses of potassium can lead to high potassium levels, or hyperkalemia. However, this condition is rare among people with regular kidney function, as the kidneys will excrete excess potassium from the body.
People with impaired kidney function may experience hyperkalemia if they consume too much potassium.
Although hyperkalemia does not usually cause symptoms, people may experienceTrusted Source:
- muscle weakness
- paralysis
- heart palpitations
- cardiac arrhythmias
Some of these effects can be life threatening.
Alternatives
Experts suggest that more than 50%Trusted Source of people with low potassium levels may also have low magnesium levels. Magnesium deficiency may also contribute to potassium deficiency by increasing potassium loss in the urine.
People with low magnesium and low potassium should receive treatment for both deficiencies.
Many manufacturers of magnesium supplements claim that they can help prevent muscle cramps. However, 2020 researchTrusted Source states that scientific studies have not been able to show that low potassium increases exercise-induced cramps, or that blood potassium levels can change quickly enough to reduce them.
Further research is necessary to confirm whether potassium can help ease muscle cramps.
Frequently asked questions about potassium supplements
Below, we answer some of the top frequently asked questions about potassium.
How much potassium is in a banana?
Medium-sized bananas typically contain 422 mgTrusted Source of potassium, which accounts for 9% of a person’s recommended daily value.
How much potassium should you get per day?
According to guidelines from the National Institutes of Health (NIH)Trusted Source, adult females should get 2,600 mg of potassium a day. Adult males should get 3,400 mg.
Children should get between 2,000–3,000 mg a day depending on their age.
What is the best form of potassium to take?
A person should prioritize getting potassium from their diet. Sources of potassium includeTrusted Source dried apricots, lentils, squash, prunes, potato, kidney beans, and bananas. Apricots offer the most potassium.
Learn more about the best food sources of potassium.
Summary
Potassium is essential for proper nerve transmission and muscle contractions. A lack of potassium in the body may cause muscle cramps, weakness, and fatigue.
People may develop hypokalemia due to an underlying medical condition, a side effect of certain medications, or following a keto diet.
Those with hypokalemia may benefit from potassium supplementation. However, they will need to see a doctor to determine the underlying cause of their hypokalemia.
People should speak with a doctor before taking any potassium supplement. Inappropriate use of potassium supplements can cause hyperkalemia, which can be life threatening.
Males and females often benefit from differing vitamin and mineral types, quantities, and combinations. With this in mind, some pharmaceutical companies develop specific formulas of supplements, vitamins, shakes, and health bars to benefit either male or female biology. A person should discuss their options with a doctor or healthcare professional who can help them decide, and choose the product they feel works best for them and their needs.
