Potassium in Kidney Disease

Why is limiting Potassium important for people with Kidney Disease? 

Potassium is an essential mineral for bodily function and can be found in a wide variety of foods. High levels of potassium can lead to complications like heart attacks, paralysis, and chest pain. Because damaged kidneys have reduced filtering capacity, most patients with CKD have to limit their potassium intake. 

• Foods high in Potassium: Bananas, oranges, potatoes, tomatoes, brown rice, bran cereals, dairy foods, whole wheat bread, pasta, beans, and nuts.
• Foods low in Potassium: Apples, peaches, carrots, green beans, white bread, pasta, white rice, cooked rice, wheat cereals, and grits.

Your Kidneys control the potassium levels in your blood and are responsible for removing excess potassium through your urine. When you have chronic kidney disease (CKD), your kidneys have a decreased ability to filter out potassium, resulting in potassium buildup in your blood, causing a condition called hyperkalemia. Hyperkalemia can pose a danger to yourself as too much potassium can cause muscle weakness, irregular heartbeat, or even sudden death. Because there are very few symptoms of hyperkalemia, people usually do not feel different when their potassium is high, however, it must be kept in mind that it can be life-threatening.

How does potassium interact with tacrolimus?

For those undergoing kidney transplantation, medications used to prevent organ rejection, such as tacrolimus, have the ability to interact with the food you eat and thus can change the effectiveness and toxicity of the drug. Because tacrolimus works to reduce sodium uptake in the body, it can impair the secretion of potassium, resulting in an accumulation of potassium, often leading to hyperkalemia. As a result, those who are taking these drugs should be sure to avoid high potassium foods and limit their daily potassium intake.

How to control potassium buildup due to kidney disease

Potassium is found in food and should be limited if your potassium is higher than your normal range. One way to lower one's potassium intake is by eating less potassium. If this is not enough, you may need to take medication to help bind extra potassium, lowering the amount of potassium in your body. When potassium buildup cannot be controlled with diet and medications, a final option to clean the extra potassium out of your blood is with dialysis, which should only be considered as a last resort and with a thorough discussion with your care team.

You should limit the amount of potassium you eat/drink to your normal range. To identify foods that are higher in potassium look to those with more than 200 milligrams per serving [usually 1/2 cup (4 ounces), unless otherwise stated]. Also, keep in mind that eating more than 1 portion (1/2 cup) of a low-potassium food can make it a higher-potassium food!

* Potassium is based on one serving

1 serving of fruit: one small piece, 1/2 cup fresh, canned or cooked fruit; 1/4 cup dried fruit, 1/2 cup juice

1 serving of vegetables: 1/2 cup fresh or cooked vegetables, 1 cup raw leafy vegetables, 1/2 cup juice 

Tips

Read food labels for potassium

• Potassium is not legally required to be listed and may not be listed even if it has potassium
• "Potassium chloride" can be used instead of salt in packaged foods (like canned soups and tomato products). Limit foods that have potassium chloride on the ingredient label
• In general, % of potassium means:
  • Low: less than 100mg or less than 3%
  • Medium: 101-200mg or 3-6%
  • High: 201-300mg or 6-9%
  • Very high: more than 301mg or over 9%
• "Serving size": tells you how big a portion is.  If you are eating 2 servings, then you are eating twice as much potassium listed
• "Potassium amount": tells you how much potassium is in 1 serving/portion of food.  If you eat 1 serving then this is how much potassium you will eat
• Measure and be aware of portions/serving  sizes
• Online or smartphone calculators can be helpful in keeping track of potassium
• Avoid salt substitutes, they usually have a lot of potassium in them (read the ingredient label)
• Use spices and herbs when cooking
• Eat smaller portions of foods high in protein
  • Meat, poultry, fish, beans, dairy, nuts
• Drain and rinse canned fruits and vegetables (do not drink or use this liquid)
• Do not drink or use juices from cooked meat
• Eat fruits + vegetables lower in potassium. Have very small portions of foods with high potassium (like one slice of tomato, a few slices of banana, half an orange)
  • Eating more than 1 portion (1/2 cup) of a low-potassium food can make it a higher-potassium food!

You can remove potassium from some high-potassium vegetables by:

You can lower the amount of potassium in most vegetables with "leaching". This can be done to remove some potassium from some vegetables

• Works well for green leafy vegetables, potatoes, sweet potatoes, carrots, beets, winter squash, and rutabagas

1. Peel the skin
2. Cut in 1/8 inch slices
3. Rinse in warm water
4. Soak in warm unsalted water, for at least 2 hours or overnight
   1. Use 10 times more water than vegetables
   2. If soaking longer than 2 hours, change the water every 4 hours
5. Drain and rinse with fresh warm water
6. Cook vegetables
   1. Use 5 times more water than vegetables
7. Drain the cooking water

Disclaimer: The UCLA Health System cannot guarantee the accuracy of such information. The information is provided without warranty or guarantee of any kind. Please speak to your Physician before making any changes.