Feb 24, 2026Kidney Health and Aging: GFR Decline, Protein Intake, and Renoprotective StrategiesGFR declines ~1 mL/min/year after age 40. In early-stage CKD, protein restriction, blood pressure control, and avoiding nephrotoxic supplements (high-dose oxalate, aristolochic acid) are the primary levers. Potassium citrate and omega-3 have supportive evidence.