Potassium is an important mineral that plays many critical roles in the human body. It is essential for fluid balance, nerve transmission, and muscle function. Many people are concerned about meeting their recommended potassium intake, especially when preparing potato dishes without the skin. Potatoes are well known as a good source of potassium, but there is some debate around whether the potato flesh alone contains enough of this key nutrient. In this article, we will examine the potassium content of potatoes with and without the skin to determine if peeling potatoes significantly reduces the potassium levels.
Potassium Content in Potatoes
Potatoes with the skin intact are packed with potassium. One medium potato (6.1 oz or 173g) with the skin provides 926mg of potassium. This supplies 20% of the 4,700mg daily recommended potassium intake for adults.[1]
However, when the potato skin is peeled off, the potassium content drops significantly. One medium peeled potato (5.3 oz or 150g) only has 542mg of potassium. This supplies just 12% of the recommended daily intake.[2]
Why Potato Skins Are High in Potassium
The potato skin is more nutrient-dense than the white flesh. It contains substantial amounts of vitamin C, vitamin B6, iron, magnesium, zinc, and fiber.[3] The skin is also rich in antioxidants like chlorogenic acid, which may have anti-cancer effects.[4]
When it comes to potassium specifically, the higher concentration in the peel comes down to the structure and composition of the different layers of the potato. The skin has more potassium-rich cells concentrated around the outside of the tuber. Meanwhile, the underlying flesh is primarily made up of starch-filled cells that store less potassium.[5]
How Much Potassium Is in Potatoes Without Skin?
While peeled potatoes still contain a decent amount of potassium, stripping away the nutrient-rich peel causes a major reduction in potassium levels.
Here is a comparison of the potassium content in medium-sized potatoes, with skin versus peeled:[1],[2]
Potassium content in potatoes with and without skin
| Potato Type | With Skin (mg potassium) | Peeled (mg potassium) |
|---|---|---|
| Russet | 926 | 542 |
| Red | 969 | 517 |
| Yukon Gold | 974 | 510 |
| Sweet | 337 | 211 |
As shown, peeling a potato removes 40-50% of the total potassium content. Sweet potatoes have the lowest levels overall, but still lose about 38% when peeled.
Do Peeled Potatoes Have Enough Potassium?
While peeled white potatoes and sweet potatoes retain decent amounts of potassium, the question remains whether this is sufficient for good health.
The recommended daily potassium intake for adults is 4,700mg.[6] Eating one medium peeled white potato would provide around 10-12% of this. A peeled sweet potato contains just 4-5% of the recommended amount.
To put this in perspective, here are some other common foods high in potassium:[7]
- Baked potato with skin: 926mg (20% DV)
- Avocado: 708mg (15% DV)
- Banana: 422mg (9% DV)
- Cooked spinach: 839mg (18% DV)
- Peeled potato: 500-542mg (10-12% DV)
- Tofu: 258mg (5% DV)
While potatoes without the skin still offer potassium, the amounts may be too low to play a starring role in meeting potassium needs for most people.
Populations at Risk for Low Potassium
Certain groups are at higher risk for potassium deficiency and may especially benefit from maximizing high potassium foods:[8]
- Older adults: Kidney function tends to decline with age, reducing potassium excretion.
- People taking certain medications: Diuretics, laxatives, steroids, antibiotics, chemotherapy, and antacids can all lower potassium levels.
- Athletes and physically active people: Potassium losses increase when sweating during intense exercise.
- Those with gastrointestinal disorders: Conditions like Crohn’s disease and ulcerative colitis can lead to low potassium absorption.
If you fall into one of these high-risk groups, be sure to include plenty of potassium-rich whole foods in your diet like potatoes with the skin, leafy greens, beans, dairy foods, fish, and unrefined grains. You may also want to check with your doctor about having your potassium level tested if concerned.
Increasing Potassium Intake from Peeled Potatoes
Peeled white and sweet potatoes can be part of a potassium-rich diet, but should not be relied on as the sole source. Here are some preparation tips to maximize the potassium you get from potatoes without skin:
- Enjoy larger portions: Eat more medium-sized peeled potatoes to get a greater total potassium boost.
- Leave some skin on: Leaving just a thin strip of peel around a potato retains more nutrients.
- Add toppings: Pair peeled potatoes with Greek yogurt, beans, salmon, avocado, nuts, or seeds to balance out the meal.
- Eat the whole potato: When you peel potatoes, eat both the flesh and the nutrient-concentrated peels to get the full package of nutrients.
- Combine with other potassium-rich foods: Avoid relying solely on potatoes and fill your diet with a variety of high potassium foods.
Key Takeaways
Potatoes are an excellent source of potassium, but most of this mineral is concentrated in the peel. Peeling a potato reduces the potassium content by about 40-50%. Peeled white potatoes and sweet potatoes still offer some potassium, but not enough to be a primary source for most people. Enjoy potatoes without skin as part of an overall potassium-rich diet, increase portion sizes modestly, leave some peel on, pair them with other potassium sources, and consume any nutrient-rich potato peels you remove. People at risk for low potassium may especially benefit from maximizing high-potassium foods.
Conclusion
Potassium is an essential mineral, and potatoes with their skins provide excellent amounts. However, peeling potatoes significantly reduces the potassium content by 40-50%. Peeled potatoes only offer about 10-12% of the recommended potassium intake per serving. While they can complement a potassium-rich diet, rely on other sources like leafy greens, beans, dairy, fish, and unrefined grains as your primary sources. Increase portion sizes of peeled potatoes, leave some skin on, pair them with other potassium-rich foods, or find ways to also eat the nutrient-dense peels. Following these preparation tips and eating potatoes as part of an overall balanced diet can help ensure adequate potassium intake for good health.