Fact check: Is there research behind "cordyceps, reishi and astragalus protect the kidneys and lower creatinine"?
The supplement category most often sold to kidney patients in Asia. We reviewed the Cochrane systematic reviews and Chinese randomised trials: low-quality evidence suggests cordyceps preparations may slightly lower creatinine, but trials were small, short and reported no hard outcomes — and for transplant recipients there are immune-stimulation and drug-interaction concerns.