Supplements
quercetin causes kidney injury
In plain terms: Is quercetin bad for your kidneys?
Refuted Supplements 🐭 Non-human evidence🔬 Includes disconfirming
Part of: 🧪 quercetin
RefutedContestedStrong support
consensus score -0.86
The evidence runs the other way: across sixteen studies quercetin protected kidneys from other damage rather than causing harm. The lone injury signal used injected, not oral, doses in rodents. What is genuinely missing is a proper human high-dose safety trial.
📅 Last reviewed: 2026-07-26 ⓘ
Evidence ladder
How far up the ladder this claim has climbed. A high consensus on a low rung means "consistent so far," not "proven in people."
Top evidence so far: Animal studies (Animal)
MechanismIn-vitroAnimalObservationalRCTMeta-analysis
How the studies fall
1 support 18 contradict 0 tested null 0 mixed · 19 sources, 19 independent groups
What the evidence shows
This one runs the opposite way to the worry. Across seventeen studies, sixteen tested quercetin as a RESCUE agent against kidney damage from something else — cisplatin, radiation, vancomycin, diclofenac, iron overload, ischaemia-reperfusion, diabetic nephropathy — and in every case it REDUCED injury markers rather than causing them.
The evidence (19)
| Source | Grade | Stance | Quality | Finding |
|---|---|---|---|---|
| Chen H, Zhan Z, Lu M, Li D, Peng J, Chen L, Yi B, Huang Z 2026 · Ecotoxicology and environmental safety | in-vitro | contradicts | low | In PM2.5-exposed HK-2 human kidney tubule cells, quercetin treatment (like FOXP1 overexpression) mitigated PM2.5-induced cellular senescence via the FOXP1/p21 pathway. In-vitro protective effect of quercetin against particulate-matter-induc |
| Zhao F, Zhou X, Chen J, Li R, Sun Y, Zhou J, Li H, Zheng G, Zhu L 2026 · Food and chemical toxicology : an international journal published for the British Industrial Biological Research Association | in-vitro | contradicts | low | In HK-2 human kidney cells, quercetin (flagged by network-toxicology/docking as a candidate antagonist) reduced diclofenac-induced inflammatory cytokine secretion and reversed diclofenac-induced dysregulation of injury-associated proteins ( |
| Elsherbiny MA, Bishr A, Sherif MM, Awad AS 2026 · The Journal of pharmacy and pharmacology | animal | contradicts | moderate | Rats given quercetin 50 or 100 mg/kg for 10 days before bilateral renal ischaemia-reperfusion surgery showed preserved kidney function, higher SOD/SLC7A11, and suppressed NF-kB/TNF-a and p53/apoptotic pathways (via SIRT-1 activation) versus |
| Hamad NS, Ghafoor DD, Rasul HO 2026 · Scientific reports | animal | supports | moderate | Healthy female Wistar rats given intraperitoneal quercetin (5, 10, 20, or 30 mg/kg every 72h for 21 days): doses >=20 mg/kg reduced weight gain and increased kidney/liver/spleen relative weight with dose-related histopathological lesions in |
| Onaolapo A et al 2026 · Research Square | animal | contradicts | low | Wistar rats fed a high-fat/high-sugar diet developed renal (and hepatic) histopathological damage plus elevated urea/creatinine; co-treatment with quercetin 100 or 200 mg/kg partially restored renal histoarchitecture and improved these mark |
| El-Hady AMA, Azzoz RM, Soliman SM, Khalil WM, Ali SA 2026 · Scientific reports | animal | contradicts | moderate | Male rats given oral quercetin 1.25 g/kg/day (very high rodent dose, 4wk course) plus curcumin before whole-body gamma irradiation (4x2Gy) showed improved creatinine/urea/uric acid and preserved renal histology versus irradiated-only contro |
| Li J, Zhang L, Li Q, Zou Y, Ni Y, Kantapan J, Dechsupa N, Wang L 2026 · Tissue & cell | animal | contradicts | low | In UUO and adenine-induced CKD/fibrosis mouse models, an engineered Iron-Quercetin metal-flavonoid complex (IronQ) decreased serum creatinine and BUN and reduced renal fibrosis markers (a-SMA, FN, Col1a1) via TGF-b1/Smad3/Egr1 inhibition. P |
| Akcakavak G, Akcakavak FK, Karatas O, Cifci AT, Kirgiz O, Kirgiz FC, Alakus H, Alakus I, Kenar ZC, Tuzcu M 2026 · Tissue & cell | animal | contradicts | moderate | Rats given vancomycin 200 mg/kg IP twice daily x7d +/- quercetin 100 mg/kg oral: quercetin co-treatment increased antioxidants (SOD/CAT/GPx), reduced MDA and inflammatory/apoptotic markers, and preserved renal structure/function versus vanc |
| Zuo A, Li S, Xie J, Huang L, Li Z, Lin J, Zhao X, Wang M 2026 · International journal of molecular sciences | in-vitro | contradicts | low | In diabetic (db/db) mice and TGF-b1-stimulated HK-2 human kidney cells, quercetin (identified as the principal bioactive component of the herbal formula Shen-Kang Recipe) bound SLC15A2/PEPT2 and suppressed epithelial-mesenchymal transition |
| Mahani FD, Heydari A, Sadeghian R, Alavi SS 2026 · Journal of biochemical and molecular toxicology | mechanism | contradicts | moderate | Narrative review of natural compounds (curcumin, quercetin, baicalein) targeting ferroptosis in drug/toxin-induced nephrotoxicity (e.g., cisplatin, adriamycin): quercetin is described as enhancing protective GPX4/Nrf2 pathways to reduce kid |
| Feng X, Bu F, Huang L, Xu W, Wang W, Wu Q 2022 · European journal of pharmacology | animal | contradicts | moderate | Meta-analysis of 20 rodent diabetic-nephropathy studies (378 animals, SYRCLE risk-of-bias assessed) found quercetin significantly improved renal index, urine protein, uric acid, urine albumin and serum creatinine (no significant effect on c |
| Zou C, Ye M 2026 · Dose-response : a publication of International Hormesis Society | animal | contradicts | moderate | In a mouse model of renal ischemia-reperfusion (I/R) injury, quercetin alleviated renal injury and inflammation in vivo and reduced H2O2-induced inflammatory responses in NRK-52E kidney cells in vitro, by inhibiting the STING-NF-kB pathway |
| Wang X, Li W, Yuan W, Wei Z, Yang Z, Zhang Z, Sun Z, Ji G, Hu H 2026 · Life (Basel, Switzerland) | animal | contradicts | moderate | In an iron-overload nephrotoxicity model (in vivo rodent + HK-2 cells in vitro), quercetin markedly reduced oxidative stress, iron accumulation and ferroptosis in renal tissue via Nrf2/xCT/GPX4 activation, attenuating renal injury. Protecti |
| Feng W, Zhou J, Zheng Y, Li Y 2026 · Pakistan journal of pharmaceutical sciences | animal | contradicts | moderate | Mouse model of aconitine-induced renal interstitial fibrosis: high-dose quercetin reduced fibrotic area by ~60% (P<0.01) and suppressed PI3K/Akt-NE/NF-kB signaling versus model controls, in a low/medium/high-dose design. Protective, anti-fi |
| Li Z, Deng H, Guo X, Yan S, Lu C, Zhao Z, Feng X, Li Q, Wang J, Zeng J, Ma X 2022 · Phytomedicine : international journal of phytotherapy and phytopharmacology | animal | contradicts | moderate | Systematic review/meta-analysis of 18 rodent studies (from 304 screened, methodological quality 7.06/10) found quercetin reduced Scr, BUN, urinary protein and improved renal pathology in diabetic-nephropathy models, with optimal effect at 9 |
| Muzamil A, Tahir HM, Ali A 2026 · Toxicon : official journal of the International Society on Toxinology | animal | contradicts | moderate | In mice, quercetin alone was safe up to 750 mg/kg with no toxicity noted, and quercetin (300-500 mg/kg, 83-100% survival) protected against Naja naja snake-venom-induced toxicity; treated kidneys showed no tubular degeneration versus venom |
| Wu M, Ye W, Ye X 2026 · Scientific reports | animal | contradicts | moderate | In high-glucose-stressed mouse podocytes and a diabetic-nephropathy mouse model (high-fat diet + streptozotocin), the quercetin glycoside QODG reduced ferroptosis (lipid peroxidation, iron accumulation) via SIRT5-mediated TFR1 desuccinylati |
| Erdemli Z, Gul M, Bulut N, Zayman E, Demirtas S, Karaaslan E, Aylaz B, Bag HG, Erdemli ME 2026 · Journal of biochemical and molecular toxicology | animal | contradicts | moderate | Wistar rats given tartrazine dye for 1 month developed nephrotoxicity (raised MDA/SOD/TOS/OSI, urea/uric acid/creatinine, histopathology, apoptosis); co-administered quercetin improved all of these biochemical and histopathological paramete |
| Yazdanpanah Z, Sobhani H, Navabi M, Jalali J, Ghasemzadeh Rahbardar M 2026 · Journal of biochemical and molecular toxicology | mechanism | contradicts | moderate | Narrative review (2021-2025 literature) concludes quercetin is nephroprotective: lowers serum creatinine/urea, restores antioxidant enzymes (SOD/CAT/GPx), and reduces apoptosis/fibrosis via Sirt1/Nrf2/HO-1 and NF-kB pathways. No data presen |
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