Nutrition Spotlight: The Phosphorus Factor in End-Stage Renal Disease

Osteodystrophy occurs when elevated blood phosphorus levels cause parathyroid hormone (PTH) levels to rise which, in turn, increases calcium release from the bones to maintain the appropriate calcium to phosphorus ratio in the blood.2 The kidneys are also responsible for activating vitamin D to increase calcium absorption in the GI tract but this process is also impaired in those with ESRD4. Elevated blood levels of calcium and phosphorus can lead to increased calcification, or stiffening, of soft tissues including blood vessels, the lungs, eyes and the heart muscle.2 Over time this can lead to the demineralization or weakening of the bones as well as an increased risk for cardiovascular complications.3, 4

Dialysis helps remove some of the phosphorus from the blood, but not enough to maintain normal blood levels. Patients on dialysis need to focus on consuming lower phosphorus foods to decrease their phosphorus intake and consequently phosphorus levels in the blood1. Examples of high phosphorus foods include dairy, nuts, dark-sodas, beans and chocolate. Lower phosphorus foods include clear-sodas, non-bran cereals, fruits and vegetables. One large egg contains 99 mg of phosphorus and can be a good high-quality protein option and poached, fried or baked eggs are a quick and affordable breakfast option – particularly when paired with other low phosphorus foods. The recipe below is great for a quick morning breakfast.

Basic Poached Eggs

egg-150x150

Ingredients:

  • 1 Egg, cold
  • Salt and Pepper

Directions:

  1. HEAT 2 to 3 inches of water in large saucepan or deep skillet to boiling. ADJUST HEAT to keep liquid simmering gently.
  2. BREAK egg into custard cup or saucer. Holding dish close to surface, SLIP egg into water.
  3. COOK egg until whites are completely set and yolks begin to thicken but are not hard, 3 to 5 minutes. Do not stir. LIFT egg from water with slotted spoon. DRAIN in spoon or on paper towels. TRIM any rough edges, if desired. SPRINKLE with salt and pepper. SERVE immediately.

References:

  1. National Kidney Foundation. Phosphorus your CKD Diet.http://www.kidney.org/atoz/content/phosphorus.cfm  Accessed April 16, 2013.
  2. Medline Plus. Phosphorus in your diet.http://www.nlm.nih.gov/medlineplus/ency/article/002424.htm Accessed April 16, 2013.
  3. National Kidney and Urologic Diseases Information Clearinghouse (NKUDIC). Chronic Kidney Disease-Mineral and Bone Disorder. http://kidney.niddk.nih.gov/kudiseases/pubs/CKD_Mineral_Bone/Accessed April 17, 2013.
  4. Moe S, Drüeke T, Cunningham J, et al. Definition, evaluation, and classification of renal osteodystrophy: A position statement from Kidney Disease: Improving Global Outcomes (KDIGO).Kidney Int. 2006; 69(11):1945-1953.