Yes, double boiling potatoes effectively removes a significant amount of potassium, often reducing it by about 50%, making them suitable for low-potassium diets, especially for people with kidney disease, by leaching the potassium into the water. This method involves peeling, slicing thinly, boiling in fresh water for about 10 minutes, draining, adding more fresh water, and cooking until tender, ensuring you discard the cooking water each time.
You can double boil the potatoes to lower potassium. First cut the potatoes in small pieces. Boil them in water until half cooked. Change the water, boil until cooked, then throw the water out.
If boiled at least 10 minutes in a large pot of water, potassium is reduced by at least half the original amount. These potatoes will still contain 100 to 200 milligrams of potassium in a 1/2-cup serving so people on a low-potassium diet are encouraged to pay attention to portion control.
Boiling potatoes and other vegetables reduces their potassium content as some of the potassium leaks into the cooking water. Potatoes that have been par-boiled (partly cooked by boiling) can then be fried, roasted or added to casseroles.
The potassium con- tent was highest in the purple Viking potato (448.1 6 60.5 mg [11.5 6 1.6 mEq]/100 g), and lowest in the Idaho potato (295 6 15.7 mg [7.6 6 0.4 mEq]/100 g). All raw potatoes had a mean potassium content of about 300 mg (7.7 mEq)/100 g or greater.
An average peeled and boiled potato (175g) contains 490mg / 12.5mmol potassium and double boiled this will reduce to 245mg / 6.3mmol potassium. Click here to learn more about preparing low potassium potatoes.
Low-Potassium Foods to Use as Substitutes
Mashed potatoes, boiled potatoes, or hash browns (all must be soaked and boiled to reduce potassium).
In case of potatoes, double-cooking method is considered the most effective way to reduce potassium from potato tissues Bower (1989). This method entails discarding the boiling water, replacing it with room-temperature water, and then boiling the potatoes again.
What are the symptoms of high potassium?
Preparation methods such as boiling, soaking, or cooling can further reduce potassium content, making potatoes an option for many patients with chronic kidney disease. With guidance from a registered dietitian nutritionist, potatoes can support kidney health and fit within a balanced diet.
Potatoes provide one of the most concentrated and affordable sources of potassium—significantly more than those foods commonly associated with being high in potassium (e.g. bananas, oranges, mushrooms, etc.).
Usually, serum potassium returns to normal after about 48 hours. Gastrointestinal (GI) excretion can be increased through the use of cation exchange resins such as sodium polystyrene sulfonate (SPS). SPS can be administered orally or rectally (as a retention enema).
Soaking food significantly reduced the potassium content in tubers and roots and leafy and cruciferous vegetables. Steam cooking and dry heating cooking also reduced potassium, although at a level lower than the other techniques.
Some vegetables are high in potassium, too, like potatoes, carrots, hard squash, beets, and sweet potatoes. This doesn't mean you can never eat these foods. If you plan ahead, you can lower the potassium. Cut the foods into small pieces and soak them in lots of water for at least 4 hours, or overnight.
Four emergency treatments to lower potassium quickly start working in minutes by shifting potassium out of the blood and into cells.
The best sources of potassium
Bring to a boil and allow to cook for about 10 – 15 minutes. After the first boiling, drain the water from the potatoes in a colander. Add the potatoes back into the pot and fill with water again. Bring the water to a boil and then cook until the potatoes are tender.
Mean potassium content was highest in the purple Viking potato (448.1 ± 60.5 mg [11.5 ± 1.6 mEq]/100 g [values are mean ± SD unless otherwise noted]), and lowest in the Idaho potato (295 ± 15.7 mg [7.6 ± 0.4 mEq]/100 g). All raw potatoes had a mean potassium content of about 300 mg (7.7 mEq)/100 g or greater.
The way you cook potatoes and vegetables can affect their potassium content. When they are boiled, some of the potassium is lost into the cooking water and this reduces the potassium content of the food. For this reason, you should: Boil vegetables/potatoes in plenty of water and make sure they are well cooked.
Potassium and phosphorus content varies with the fish variety–catfish, cod, orange roughy, sea bass and sole are among the lowest. Salmon contains higher amounts of potassium and phosphorus but can still be worked into a kidney diet by combining it with lower potassium sides and adjusting phosphorus binders if needed.
Pasta and rice are much lower in potassium than potatoes. For rice or pasta dishes, you can use half large tin (200 grams) of canned tomatoes instead of potato.
Normal potassium lab values for people with chronic kidney failure is 3.5-5.0 mEq/L. For dialysis patients the goal is 3.5 to 5.5 . Potassium levels above 6.0 are dangerous and require a low potassium diet, medication change and/or dialysis to help reduce potassium to a safe range.