6-tips diet: a simplified dietary approach in patients with chronic renal disease. A clinical randomized trial.

Background: The beneficial effects of dietary restriction of proteins in chronic kidney disease are widely recognized; however, poor compliance to prescribed low-protein diets (LPD) may limit their effectiveness. To help patients to adhere to the dietary prescriptions, interventions as education programmes and dietary counselling are critical, but it is also important to develop simple and attractive approaches to the LPD, especially when dietitians are not available. Therefore, we elaborated a simplified and easy to manage dietary approach consisting of 6 tips (6-tip diet, 6-TD) which could replace the standard, non-individualized LPD in Nephrology Units where dietary counselling is not available; hence, our working hypothesis was to evaluate the effects of such diet vs a standard moderately protein-restricted diet on metabolic parameters and patients' adherence.

Methods: In this randomized trial, 57 CKD patients stage 3b-5 were randomly assigned (1:1) to receive the 6-TD (Group 6-TD) or a LPD containing 0.8 g/kg/day of proteins (Group LPD) for 6 months. The primary endpoint was to evaluate the effects of the two different diets on the main "metabolic" parameters and on patients' adherence (registration number NCT01865526).

Results: Both dietary regimens were associated with a progressive reduction in protein intake and urinary urea excretion compared to baseline, although the decrease was more pronounced in Group 6-TD. Effects on serum levels of urea nitrogen and urinary phosphate excretion were greater in Group 6-TD. Plasma levels of phosphate, bicarbonate and PTH, and urinary NaCl excretion remained stable in both groups throughout the study. 44 % of LPD patients were adherent to the dietary prescription vs 70 % of Group 6-TD.

Conclusions: A simplified diet, consisting of 6 clear points easily managed by CKD patients, produced beneficial effects either on the metabolic profile of renal disease and on patients' adherence to the dietary plan, when compared to a standard LPD.