„High protein intake damages the kidneys.”

No evidence in healthy kidneys: a meta-analysis of RCTs (Devries 2018, n=1,358) found 1.5–2.2 g/kg protein didn't worsen GFR; filtration rises adaptively. The myth stems from ALREADY damaged kidneys (CKD 3+), where protein restriction (0.6–0.8 g/kg) really does slow decline. In healthy older adults the opposite is the problem: too little protein causes sarcopenia. Check eGFR, and if normal, 1.2–1.6 g/kg is safe.

Last reviewed: 6 September 2026

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