Mustard is not high in potassium. A teaspoon of prepared yellow mustard contains roughly 7 milligrams of potassium, which is a negligible amount compared to the 4,700 mg daily value. Even generous servings barely register on a potassium scale, making mustard one of the lowest-potassium condiments available.
Potassium in Different Types of Mustard
Yellow mustard, the most common variety, delivers about 7.5 mg of potassium per teaspoon. Most people use one to two teaspoons at a time, so a typical serving contributes fewer than 15 mg. For context, a medium banana has around 420 mg.
Dijon mustard contains slightly more potassium because of its higher mustard seed concentration, but the numbers are still very low. A one-ounce serving (about two tablespoons) of Dijon provides roughly 42.5 mg of potassium, which is 1% of the daily value. Whole grain, spicy brown, and honey mustard varieties all fall in a similar range. No common type of prepared mustard comes close to the 200 mg per serving threshold that the National Kidney Foundation uses to classify a food as “high potassium.”
Mustard Seeds vs. Prepared Mustard
The raw ingredient tells a slightly different story. Ground mustard seeds contain about 15 mg of potassium per teaspoon. That’s roughly double what you get in prepared yellow mustard, because the condiment version is diluted with vinegar, water, and other ingredients. Still, even using mustard powder as a dry seasoning keeps you well within low-potassium territory. You would need to consume an impractical amount of mustard seeds to reach a meaningful potassium intake.
Mustard on a Kidney-Friendly Diet
If you’re managing kidney disease or tracking potassium for another medical reason, mustard is considered safe. UC Davis Health includes dried mustard on its renal grocery list of foods appropriate for a kidney diet, and DaVita, a major kidney care provider, specifically notes that potassium and phosphorus in mustard are both low at less than 7 mg per teaspoon. Oriental-style mustard paste and mustard sauce are similarly low.
One thing to watch for: low-sodium mustard products. Some manufacturers reduce sodium by substituting potassium chloride for regular salt. The National Kidney Foundation warns that these salt substitutes can contain substantial amounts of potassium, sometimes more harmful than the sodium they replace. If you’re on a potassium-restricted diet, check the ingredient label for potassium chloride before buying a “reduced sodium” or “no salt added” mustard. Standard mustard, which contains only 25 to 65 mg of sodium per teaspoon, is already relatively low in sodium without needing a reformulated version.
How Mustard Compares to Other Condiments
Mustard sits at the very bottom of the potassium scale among common condiments. Here’s how a typical serving stacks up:
- Yellow mustard (1 tsp): ~7 mg potassium
- Ketchup (1 tbsp): ~55 mg potassium
- Soy sauce (1 tbsp): ~40 mg potassium
- Barbecue sauce (2 tbsp): ~70 mg potassium
- Tomato salsa (2 tbsp): ~80 mg potassium
Mustard’s advantage is that it adds flavor with almost no potassium, very little sodium by condiment standards, and virtually no calories. For anyone trying to keep potassium intake low while still making food taste good, it’s one of the better options in the fridge.