Hemodialysis (HD) patients trained in food preparation and cooking techniques that reduce dietary phosphorus tend to have lower serum phosphorus levels after a year, a new study finds.
Ivica Vrdoljak, MD, of Dr Josip Bencˇevic´ General Hospital, Ines Panjkota Krbavčić, PhD, professor of Food Technology and Biotechnology at the University of Zagreb in Croatia, and colleagues randomly assigned 47 HD patients to cooking or non-cooking (control) groups. Patients had serum phosphate levels above 1.42 mmol/L, abnormal calcium levels, or parathyroid hormone levels above 65 pg/mL. Everyone received phosphate binder therapy (calcium carbonate, sevelamer, or both) to prevent or treat hyperphosphatemia.
A dietitian taught all patients how to select low phosphorus foods while maintaining adequate protein during a 3-day program and 15-minute individual sessions (weekly for 2 months). Plant foods were encouraged because their phosphorus content is poorly absorbed. Participants learned how to control their intake of fluid, calcium, and sodium, and maintain the phosphorus-calcium balance.
In addition to nutritional advice, the cooking group received instruction in phosphorus-reducing techniques in food preparation and cooking while maintaining protein intake. They were taught to soak meat in water for an hour before cooking, boil foods, and stew foods in oil, among other methods.
During dialysis sessions, patients received prepared meals. The control group received standard meals for dialysis patients, while the cooking group received low phosphorus meals with similar protein content.
Although not a statistically significant difference, the cooking group reduced their serum phosphorus slightly more over 1 year than the control group: -0.3 vs -0.2 mmol/L, on average. The cooking group also reduced their number of phosphate binder pills over the year, whereas the control group only did so for 3 months. Importantly, neither serum albumin nor normalized protein catabolic rate was adversely affected in the intervention group, despite their lower intake of dietary phosphorus.
HD patients instructed in low phosphorus cooking techniques “can experience a significant reduction in dietary phosphorus intake and maintain low levels of serum phosphate with a minimum risk of malnutrition, contributing to the prevention and treatment of hyperphosphatemia,” Dr Vrdoljak and colleagues concluded in Hemodialysis International.
A 2015 study by N Jiang et al. likewise found that low phosphorus cooking techniques improves hyperphosphatemia in peritoneal dialysis patients (Nutr Metab Cardiovasc Dis. 2015; 25:846–852). http://www.ncbi.nlm.nih.gov/pubmed/26141941
1. 1. Vrdoljak I, Panjkota Krbavcic I, Bituh M, Leko N, Pavlovic D, Vrdoljak Margeta T.
The impact of education and cooking methods on serum phosphate levels in patients on hemodialysis: 1-year study. Hemodial Int. 2016. doi:10.1111/hdi.12468.