Based on PubMed | Does drinking green tea slow the progression of chronic kidney disease?

Drinking green tea has not been proven to slow chronic kidney disease (CKD) progression in humans, although it may offer limited cardiovascular and antioxidant benefits in certain situations. Evidence in people with CKD is sparse and short term; one small trial in dialysis patients showed improved blood vessel function after 4 weeks of green tea but did not measure kidney function or show changes in markers like protein in the urine. ^[1] Current clinical guidance for slowing CKD emphasizes controlling the underlying causes (such as diabetes and high blood pressure), managing complications, and making targeted diet and lifestyle changes rather than relying on specific beverages or supplements. ^{[2] [3]} General kidney‑health recommendations include limiting salt, managing blood pressure and blood sugar, and choosing balanced diets, which are more clearly supported for preserving kidney function over time. ^[4]

What the research shows

• Human data are limited. A small randomized study in people on chronic dialysis found that 1 month of green tea (about 5 g tea leaves/day) improved endothelial function (flow‑mediated dilation), but there were no significant changes in inflammatory markers, oxidative stress markers, or circulating endothelial progenitor cells, and the study did not assess eGFR or proteinuria in non‑dialysis CKD. ^[1]
• Mechanistic and animal studies suggest catechins especially EGCG (epigallocatechin‑3‑gallate) can reduce oxidative stress and inflammation in kidney injury models, pathways relevant to CKD; however, results in animals do not establish benefit in human CKD progression. ^[5]
• Reviews highlight theoretical renoprotective effects of green tea polyphenols against oxidative stress–related kidney damage, but they also acknowledge the lack of high‑quality human trials demonstrating slower CKD progression. ^[6]

How green tea fits into CKD care

• CKD progression is most reliably slowed by treating the cause (for example, tight control of diabetes and blood pressure) and using evidence‑based therapies such as ACE inhibitors/ARBs, SGLT2 inhibitors (when appropriate), dietary sodium reduction, and protein moderation as advised by a clinician. ^{[2] [3]}
• Healthy‑eating guidance for CKD focuses on lowering sodium, controlling blood pressure and weight, and, in many cases, moderating protein intake; these strategies are associated with better kidney and heart outcomes and are more supported by clinical evidence than green tea consumption alone. ^{[4] [7]}

Safety considerations for green tea in CKD

• Moderate green tea drinking is generally considered safe for most people and is not linked to higher kidney stone risk, although individual tolerance varies. ^{[8] [9]}
• Concentrated green tea extracts and high doses can cause side effects, particularly liver enzyme elevations; labels advise taking extracts with food and avoiding them if you have liver problems. ^{[10] [11]}
• Green tea (especially extracts) can interact with certain medications by affecting drug‑metabolizing enzymes and transporters (for example, CYP3A4, UGTs, OATP1A2), and it contains caffeine that may cause insomnia, palpitations, or nausea. ^{[12] [13]}
• For people with CKD, beverage choice should also consider potassium and fluid limits set by your care team; brewed green tea typically has low potassium, but total fluid intake still matters in advanced CKD and dialysis.

Practical guidance if you enjoy green tea

• It may be reasonable to include moderate amounts of brewed green tea as part of an overall kidney‑friendly lifestyle, primarily for general cardiovascular wellness and hydration, rather than as a treatment to slow CKD. ^[4]
• Avoid high‑dose green tea extracts unless specifically discussed with your clinician, given potential liver risks and drug interactions, and because they have not been shown to slow CKD progression. ^{[10] [12]}
• Keep the fundamentals first: control blood pressure and blood sugar, limit sodium, follow individualized protein and phosphorus guidance, maintain a healthy weight, avoid NSAID overuse, and stay up to date with medications known to protect kidneys. ^{[2] [7] [4]}

Bottom line

• There is no conclusive human evidence that drinking green tea slows the decline of kidney function in CKD. ^[1]
• Green tea’s antioxidants may help vascular function and oxidative stress in theory and in animal models, but these findings have not translated into proven reductions in CKD progression in clinical trials. ^{[5] [6]}
• The most effective strategies to slow CKD progression remain medical management of underlying conditions and established lifestyle measures, with green tea if used best viewed as a safe, moderate beverage choice rather than a disease‑modifying therapy. ^{[2] [3] [4]}