Obesity has been proposed as a possible potentiator of CKD progression; however, reliable data remain sparse. Many observational studies have suggested that among patients with advanced CKD who are dialysis-dependent, and particularly hemodia- lysis-dependent, clinical outcomes might actually be better for overweight individuals than for non-overweight indivi- Other studies have reported conflicting results.60 It is possible that these observations are due to reverse causality, with the results driven by underlying malnutrition or inflammation in the lower-weight patients and they may also reflect differences in the proportions of muscle and fat in patients with CKD compared with people without CKD. These data should therefore be interpreted with caution. For overweight individuals, the method used to reduce body weight may be important within the context of CKD. Popular and widely recommended weight-loss diets are commonly high in potassium and protein and may therefore increase risks of hyperkalemia and CKD progression in patients with CKD. As the potential benefits and harms have not been specifically addressed in the CKD population, the use of these diets is not recommended. Overall, the available data suggest that achieving or maintaining a body weight in the healthy range will lead to improved BP levels and better long-term CKD outcomes. This is particularly clear for individuals with CKD stages 1 2. Caution should be exercised in patients with more advanced CKD, because malnutrition may be associated with adverse outcomes. Since a high weight may be protective in CKD 5D patients, there could be risks associated with encourag- ing weight loss in those with advanced CKD. Hence, Recommendation 2.3.1 was graded 1D. 2.3.2: We recommend lowering salt intake to o90 mmol (o2 g) per day of sodium (corresponding to 5 g of sodium chloride), unless contraindicated. (1C) RATIONALE K Lowering salt intake reduces BP in the general population. 