CST3 and chronic kidney disease: First, patients with AKI were excluded from enrollment, as were those with other acute comorbidities, since their inclusion could have resulted in false baseline levels of serum creatinine or cystatin C. For this reason, we selected only patients with stable renal function for at least 3 months (following the K-DIGO guideline definition of CKD stages) in order to measure the real impact of a new dietary regimen and avoid the potential external bias due to medical therapies for other conditions such as AKI or AKD.