Decaf Coffee’s Effect on the Kidneys: Yes, It Can Help

Your kidneys do not get a lot of airtime unless something has gone wrong with them, at which point they get everyone’s full and undivided attention. For anyone who has been told to watch their caffeine intake, or who is managing kidney disease or high blood pressure, the question of whether decaf coffee is safe is a genuinely important one. The internet, characteristically, has not made this easier to answer.

We are not going to go all yoga-crystal-dreamcatcher-mindful-woo-woo on you here. What we do have is a growing body of peer-reviewed research on coffee, caffeine and kidneys, and the picture it paints is considerably more reassuring than the corner of the internet that is convinced everything you enjoy will eventually do you in.

Here is what the evidence actually says.

Is coffee bad for the kidneys?

Numerous studies have concluded that coffee is unlikely to harm the kidneys or cause chronic kidney disease. In fact, research suggests several benefits to consuming a moderate amount of coffee, including improved energy levels and metabolism due to caffeine, as well as the antioxidant properties of polyphenols in coffee. However, moderation is key, especially for individuals with high blood pressure or kidney stones.

A 2022 study found a lower risk of kidney injury among daily coffee drinkers, with higher consumption associated with greater risk reduction. A study of 14,209 people aged 45 to 64 found that coffee drinkers had an 11 per cent lower risk of developing chronic kidney disease over eight years. A 2025 analysis of nearly 50,000 US adults found that drinking more than one and a half cups daily was linked to approximately 24 per cent lower odds of chronic kidney disease, with that association holding even after adjusting for age, blood pressure and diabetes.

Studies on coffee and kidney disease

Population-based epidemiological studies have indicated a potential protective effect of coffee consumption on kidney function. However, excessive caffeine intake, particularly from caffeinated coffee, may lead to a decline in kidney function in certain populations. A large prospective study published in Scientific Reports, following 5,851 overweight and obese adults aged 55 to 75 with metabolic syndrome, found that drinking more than two cups of caffeinated coffee per day was associated with greater kidney filtration rate decline over one year.

Decaffeinated coffee showed no such association. The researchers found no connection between decaf consumption and kidney filtration rate decline whatsoever. The compound associated with kidney filtration decline in high-risk populations is caffeine. Remove it and the association disappears.

The genetics angle

One of the more striking recent findings is that the relationship between coffee and kidney health is partly genetic. Research from the Universities of Toronto and Padova found that people with the slow-metaboliser variant of the CYP1A2 gene, roughly half the population, process caffeine significantly more slowly. In these individuals, those who drank three or more cups of regular coffee daily were 2.7 times more likely to develop kidney dysfunction. In fast metabolisers, the same intake produced no elevated kidney risk at all.

The lead researcher was clear on the implications: since decaffeinated coffee is virtually devoid of caffeine, those who consume decaf would not have a higher risk of kidney dysfunction regardless of their genetics. Your sentient bucket of porridge between the ears cannot claim it was not warned.

Coffee and genetic kidney disease

Contrary to past concerns, current clinical studies have not found coffee consumption to be a risk factor for the progression of autosomal dominant polycystic kidney disease.

Does coffee increase the risk of kidney stones?

The evidence points the other way. A study published in the American Journal of Kidney Diseases, using data from 571,657 participants across the UK Biobank and FinnGen studies, found that going from one cup to one and a half cups of coffee per day was associated with a 40 per cent reduction in kidney stone risk. The National Kidney Foundation described the study’s design as strengthening the evidence that coffee and caffeine can actively prevent kidney stone formation.

That said, regular coffee consumption has been associated with calcium oxalate stone formation in individuals already prone to them. Patients with a history of calcium oxalate kidney stones should consider their coffee intake as a potential factor and discuss it with their GP.

Does coffee increase the risk of kidney cancer?

The relationship between coffee consumption and kidney cancer is mixed. Studies suggest a reduced risk of renal cell carcinoma with caffeinated coffee. The relationship with decaffeinated coffee and clear cell renal cell carcinoma requires further research before firm conclusions can be drawn.

Coffee, hypertension and kidney disease

While caffeinated coffee may cause a short-term increase in blood pressure, particularly in older individuals and non-regular coffee drinkers, moderate consumption of up to three to four cups daily does not appear to increase the risk of kidney disease in healthy individuals. Those with high blood pressure should consult their healthcare provider regarding caffeine intake.

Decaf and hypertension

Even decaffeinated coffee has been associated with some increase in nervous system activity and blood pressure in certain studies, suggesting that compounds other than caffeine may play a role. That said, decaf removes the primary blood pressure driver and is generally the recommended switch for people whose blood pressure is caffeine-sensitive.

How to safely enjoy coffee with kidney disease

For individuals with kidney disease, the National Kidney Foundation recommends limiting coffee intake, opting for black coffee to avoid the phosphorus and potassium in creamers and milk, counting coffee in fluid allowances, and considering decaf coffee or decaf teas as a sensible alternative. An 8-ounce cup of black coffee contains around 116 mg of potassium, which is considered low. A cafe latte without flavoured syrup adds 183 mg of phosphorus and 328 mg of potassium on top. The problem, as ever, is almost always what goes into the cup rather than the cup itself.

For people with advanced kidney disease or on dialysis, fluid restrictions apply and all coffee intake should be discussed with a nephrologist. For anyone who has had a kidney transplant, decaf may be recommended as part of a post-transplant dietary protocol.

Frequently asked questions

The bottom line

Current research suggests that decaf coffee is generally safe for kidney health, with the antioxidant benefits of coffee present in both caffeinated and decaffeinated versions. For anyone managing caffeine sensitivity, high blood pressure or kidney disease, decaf removes the primary compound of concern while keeping everything that makes coffee worth drinking. Consulting a healthcare provider for personalised recommendations is always advised.

Browse the full I Love Decaf range of decaf coffee, decaf tea and naturally caffeine-free herbal and fruit infusions.

References

1. Antwi SO, Eckel-passow JE, Diehl ND, et al. Coffee consumption and risk of renal cell carcinoma. Cancer Causes Control. 2017;28(8):857-866. doi:10.1007/s10552-017-0913-z
2. Girardat-rotar L, Puhan MA, Braun J, Serra AL. Long-term effect of coffee consumption on autosomal dominant polycystic kidneys disease progression: results from the Suisse ADPKD, a prospective longitudinal cohort study. J Nephrol. 2018;31(1):87-94. doi:10.1007/s40620-017-0396-8
3. Center for Science in the Public Interest. Caffeine chart.
4. Sirotkin AV, Kolesárová A. The anti-obesity and health-promoting effects of tea and coffee. Physiol Res. 2021 Apr 30;70(2):161-168. doi: 10.33549/physiolres.934674
5. Kennedy OJ, Roderick P, Poole R, et al. Coffee and kidney disease. Int J Clin Pract. 2017;71(8):e12980. doi: 10.1111/ijcp.12980
6. Poole R, Kennedy OJ, Roderick P, et al. Coffee consumption and health: umbrella review of meta-analyses of multiple health outcomes. BMJ. 2017 Nov 22;359:j5024. doi: 10.1136/bmj.j5024
7. Harvard Medical School. Coffee and your blood pressure.
8. Tommerdahl KL, Hu EA, Selvin E, et al. Coffee consumption may mitigate the risk for acute kidney injury: results from the atherosclerosis risk in communities study. Kidney International Reports. 2022;7(7):1665-1672. doi: 10.1016/j.ekir.2022.04.091
9. Haghighatdoost F, Sadeghian R, Abbasi B. The Associations Between Tea and Coffee Drinking and Risk of Calcium-Oxalate Renal Stones. Plant Foods Hum Nutr. 2021 Dec;76(4):516-522. doi: 10.1007/s11130-021-00933-4
10. Wijarnpreecha K, Thongprayoon C, Thamcharoen N, Panjawatanan P, Cheungpasitporn W. Association of coffee consumption and chronic kidney disease: A meta-analysis. Int J Clin Pract. 2017;71(1) doi:10.1111/ijcp.12919
11. Yamagata K. Do Coffee Polyphenols Have a Preventive Action on Metabolic Syndrome Associated Endothelial Dysfunctions? An Assessment of the Current Evidence. Antioxidants (Basel). 2018 Feb 4;7(2):26. doi: 10.3390/antiox7020026
12. Díaz-López A, Paz-Graniel I, Ruiz V, et al. Consumption of caffeinated beverages and kidney function decline in an elderly Mediterranean population with metabolic syndrome. Sci Rep. 2021;11(1):8719. doi: 10.1038/s41598-021-88028-7
13. National Kidney Foundation: Coffee and Caffeine Can Reduce Kidney Stones Risk. American Journal of Kidney Diseases (2024)
14. Mahdavi S et al. CYP1A2 gene variant and coffee-related kidney dysfunction risk. Universities of Toronto and Padova (2023)
15. National Kidney Foundation: Coffee and Kidney Disease, Is it Safe?