Reading Labels to Control Phosphorus in the Dialysis Diet

People with kidney disease, especially those on dialysis, need to monitor the amount of phosphorus in the foods they consume.

What is phosphorus?

Phosphorus is the second most common mineral in the body, after calcium. Phosphorus, also called phosphate, is absorbed in the small intestines, and about 85 percent of it is stored in the bones. It helps the body:

• use and store energy
• build strong bones and teeth
• maintain a normal pH balance
• activate enzymes and hormones
• build cell membranes

Nutritionists recommend that healthy adults with normal kidney function get between 700 mg and 1,200 mg of phosphorus each day. However, the average American diet contains much greater amounts of phosphorus, partially due to additives in processed foods.

Extra phosphorus is removed by healthy kidneys, and levels start to rise with kidney disease even before a person needs dialysis. When kidneys fail, phosphorus can build up in the blood, a condition called hyperphosphatemia. This condition contributes to a wide range of problems such as bone disease, joint pain, severe itching and many more.

How much phosphorus does dialysis remove?

Neither hemodialysis or peritoneal dilaysis (PD) are very effective at eliminating phosphorus from the body. The amount of phosphorus removed in a dialysis treatment ranges from 250 to 1,000 mg per treatment. This number is affected by the pre-dialysis phosphorus level, the type of dialyzer and the amount of dialysis received.

Foods high in phosphorus

Your dietitian will likely recommend that you limit or avoid foods that are high in phosphorus. Foods that naturally contain high phosphorus levels include milk and some milk products, amaranth, bran, brown rice, millet, quinoa, spelt, dried beans and peas, nuts and seeds, organ meats, sardines, beer, corn tortillas and chocolate. Foods that contain high phosphorus due to phosphate additives include some types of baking powder, pancakes, waffles, biscuits, refrigerated bakery products, instant puddings and sauces, processed and enhanced meats, colas and many powdered, bottled or canned beverages.

The following chart shows some high-phosphorus foods and suggests some lower-phosphorus substitutes.

Checking nutrition labels for hidden phosphorus

Although many nutrients are listed on the nutrition labels of the foods you buy, it’s not required by law for phosphorus to be listed. Therefore, it’s rarely included on the label. Some foods, such as cereals, list the percent Daily Value for phosphorus. If milligrams or percent Daily Value are listed, use the following as a guide to elevate the amount of phosphorus in foods:

Spot hidden phosphorus by checking for variations of the word phosphate, such as phosphoric acid, sodium aluminum phosphate, pyrophosphate, polyphosphates and calcium phosphate. Remember to also check for phosphorus on the labels on medicines and supplements.

Getting enough nutrition while limiting phosphorus

If you’re a dialysis patient who has to limit phosphorus in your kidney-friendly diet, it’s still possible for you to get the right amount of nutrition. The key is to select from the foods recommended on your eating plan and to pay attention to portion size. Some phosphorus-containing foods, like meat, fish and eggs, are required to provide adequate protein in the diet.

The role of phosphate binders

Usually diet modifications alone won’t keep phosphorus levels in a safe zone. This is where phosphate binders can help. Phosphate binders decrease the absorption of phosphorus from food into the blood.

Your doctor and/or dietitian will tell you how many binders to take when you eat.

Control phosphorus today

Join DaVita Diet Helper, the quick and easy way to get meal plans for your low-phosphorus kidney diet.