4 Must-Avoid Carbs on Your Renal Diet

RenalTracker Team: April 12, 2019

It's no question that when you need more energy for your daily activities, especially when you live actively, you'll need starchy foods (usually called carbs).

But when you have CKD, indulging too much on carbs is a big no. This is because most carbohydrate- and sugar-rich foods are also rich in sodium, potassium, and phosphorus. 

Here are some carbs-to-avoid, in consideration to your kidneys:

1. Whole-Wheat and Whole-Grain Bread

Most regular people like whole-wheat bread because it has more fiber and nutrients. However, on a low-potassium, low-phosphorus renal diet, you'll have to settle with refined, white flour bread.

Whole-wheat and whole-grain bread have a lot of phosphorus and potassium within them. They contain about 69 mg of potassium and 57 mg of phosphorus per serving. White bread, on the other hand, contains only 28 mg of both nutrients.

Sodium is often also high for both kinds of bread, so it's advisable to read labels thoroughly and look for low-salt or low-sodium options.

2. Brown Rice

Same goes for brown-rice lovers; if you have CKD, chances are, you'll have to switch to an alternative, like white rice.

Brown rice, when cooked, contains about 154 mg of potassium and 150 mg of phosphorus. White rice, however, contains only less than 50% of that for both nutrients.

Aside from white rice, there are also other alternatives, such as:

  • buckwheat
  • bulgur
  • couscous
  • pearled barley

3. Oatmeal and Other Bran Cereals

A cup of oatmeal, when cooked, contains about 143 mg of potassium and 157 mg of phosphorus. This is why oatmeal is another food-to-avoid for kidney disease patients.

Also, bran cereals technically have the same rule as whole-wheat / whole-grain breads - the more bran in the food, the higher the potassium and phosphorus content.

Thankfully, the National Kidney Foundation (NKF) has a list of cereal recommendations. Here are a few of the cereal brands that have low potassium and low phosphorus for your renal diet:

  • Apple Jacks
  • Barbara's (Cinnamon Puffins, Corn Flakes, etc.)
  • Cascadian Farms (Chocolate O's, Cinnamon Crunch, etc.)
  • Corn Pops
  • Fruit Loops
  • Health Valley Rice Crunch-Ems
  • Honey Smacks
  • Kashi (Honey Sunshine, Indigo Morning, etc.)
  • Puffed Rice
  • Trix

4. Potatoes

When it comes to starchy foods, potatoes easily come to mind. It's also a very versatile vegetable because of the myriad ways it can be prepared and served.

However, they are also saturated with potassium. On average, a potato contains about 610 mg while sweet potatoes have about 540 mg of potassium, when baked.

But there is a way to reduce potassium content in these veggies: leaching. There are two common ways to do this:

  1. To reduce their potassium content by about 50%, simply chop up potatoes into small, thin pieces and boil them in water for 10 minutes, at least.
  2. You can also peel, dice, and soak potatoes for 2-4 hours in tap water. This is also known as double cooking, and has been proven to leach off more potassium from the vegetable.
Other must-avoid carbs include:
  • dark-colored colas
  • granola
  • hard candies
  • soft drinks
  • sugar

We should always be careful with all that we eat. Sometimes, what's good for us before is dangerous to us now.

Best advice we can give, however, is this: if you're not sure about a certain food item, always ask the opinion of a professional, whether it be your doctor or your dietitian. That way, you can be sure that what you're getting are only the good things for your kidneys.


17 Foods to Avoid If You Have Bad Kidneys - Healthline:


Choosing the Right Breakfast Cereal with CKD - National Kidney Foundation:


Kidney-friendly diet for CKD - American Kidney Fund: