Phosphate and Diet
Phosphate is a mineral that is important for bone metabolism. As kidney function declines phosphate builds up resulting in adverse side effects (itchy skin, painful joints and bone breakdown).1 It is imperative to control phosphate intake in diet to prevent phosphate build up. High and moderate phosphate containing foods such as milk products, proteins and nuts will need to be limited.1 A registered dietician can serve as a partner in creating an appropriate meal plan.
Phosphate additives and label reading
It is not required to list the phosphorus content of food products on the nutrition label.1 Ensure that your patients look for hidden sources of phosphorus, such as phosphoric acid and sodium phosphate. Most processed meats and many beverages, especially colas, contain added phosphates. Phosphate intake should be restricted to 800-1000 mg/day when the upper level of serum phosphorus is reached (>1.80 mmol/L). 1
STRATEGIES TO LIMIT DIETARY PHOSPHORUS INTAKE
Optimize the types and sources of dietary phosphorus intake.1
• Consume less processed foods and colas
◦ Natural sources of phosphorus (meat, dairy) have organified phosphorus, which have a lower bioavailability
▪ Phosphorus found in many plant sources (ie. phytate) has particularly poor oral absorption in humans
◦ Processed foods have phosphate-containing food additives (polyphosphates, potassium phosphate, etc)
An RCT conducted by Sullivan and colleagues(2) showed that hemodialysis patients who were given focused dietary counselling (ie. educated on reading product labels, educated on how to substitute high phosphorus foods with lower phosphorus options) had lower mean serum phosphate levels than patients receiving standard counselling.
BOTTOM LINE:
• Dietary phosphorus restrictions are effective at lowering serum phosphate levels in patients with hyperphosphatemia due
to CKD
• Intensive dietician support and close monitoring/follow-up is required to ensure that dietary restrictions are employed
appropriately and safely
Phosphorous guidelines for choosing foods(1)
Phosphate additives and label reading
It is not required to list the phosphorus content of food products on the nutrition label.1 Ensure that your patients look for hidden sources of phosphorus, such as phosphoric acid and sodium phosphate. Most processed meats and many beverages, especially colas, contain added phosphates. Phosphate intake should be restricted to 800-1000 mg/day when the upper level of serum phosphorus is reached (>1.80 mmol/L). 1
STRATEGIES TO LIMIT DIETARY PHOSPHORUS INTAKE
Optimize the types and sources of dietary phosphorus intake.1
• Consume less processed foods and colas
◦ Natural sources of phosphorus (meat, dairy) have organified phosphorus, which have a lower bioavailability
▪ Phosphorus found in many plant sources (ie. phytate) has particularly poor oral absorption in humans
◦ Processed foods have phosphate-containing food additives (polyphosphates, potassium phosphate, etc)
An RCT conducted by Sullivan and colleagues(2) showed that hemodialysis patients who were given focused dietary counselling (ie. educated on reading product labels, educated on how to substitute high phosphorus foods with lower phosphorus options) had lower mean serum phosphate levels than patients receiving standard counselling.
BOTTOM LINE:
• Dietary phosphorus restrictions are effective at lowering serum phosphate levels in patients with hyperphosphatemia due
to CKD
• Intensive dietician support and close monitoring/follow-up is required to ensure that dietary restrictions are employed
appropriately and safely
Phosphorous guidelines for choosing foods(1)
Reference
1. The Kidney Foundation of Canada. Phosphorous (phosphate) and chronic kidney disease. 2010. Web 11 Jan 2013. <http://www.kidney.ca/document.doc?id=801>
2. Sullivan C, Sayre SS, Leon JB, Machekano R, Love TE, Porter D, Marbury M, Sehgal AR.: Effect of food additives on hyperphosphatemia among patients with end-stage renal disease: A randomized controlled trial. JAMA 301: 629-635, 2009.
1. The Kidney Foundation of Canada. Phosphorous (phosphate) and chronic kidney disease. 2010. Web 11 Jan 2013. <http://www.kidney.ca/document.doc?id=801>
2. Sullivan C, Sayre SS, Leon JB, Machekano R, Love TE, Porter D, Marbury M, Sehgal AR.: Effect of food additives on hyperphosphatemia among patients with end-stage renal disease: A randomized controlled trial. JAMA 301: 629-635, 2009.