Navdeep Tangri, MD, is a professor of medicine at the University of Manitoba in Canada. 

Navdeep Tangri, MD

Serum bicarbonate and safety measures did not differ significantly from oral sodium bicarbonate in a 36-person, 12-month trial.

Oral alkali therapy is recommended for metabolic acidosis in 

, but treatment rates remain low, largely because of side effects and poor tolerability.¹ A 12-month randomized trial tested weekly grocery delivery of base-producing fruits and vegetables as another option.

Can Delivering Fruits and Vegetables Address CKD Acidosis? With Navdeep Tangri, MD

Navdeep Tangri, MD, professor of medicine at the University of Manitoba, presented the ReDACKD feasibility trial at the 

American Society of Nephrology (ASN) Kidney Week 2026

 in Denver, Colorado. Most participants completed the full year. Serum bicarbonate did not differ significantly between produce delivery and sodium bicarbonate, although the trial was too small to show whether the 2 approaches are equally effective.¹

“I think clinicians should think about fruits and vegetables and sort of direct food delivery as a possible and viable alternative to medical therapy, and I shouldn’t say alternative. Perhaps I should say complementary to medical therapy,” Tangri said in an interview with 

. “I’m a very evidence-based, clinical trials-based person. I think medical therapy is terrific, but I also think providing appropriate nutrition can also help lower risk factors and work together with the medicine and work safely.”

Testing Fruit and Vegetable Delivery Against Sodium Bicarbonate

Metabolic acidosis is a common complication of CKD and is associated with accelerated disease progression. Although guidelines recommend oral alkali therapy, investigators noted that tolerability concerns, including the risk of worsening hypertension, limit its use.¹

Earlier work by Nimrit Goraya, MD, Donald E. Wesson, MD, and colleagues found that 1 year of fruits and vegetables or sodium bicarbonate improved metabolic acidosis in people with stage 4 CKD due to hypertensive kidney disease, without producing hyperkalemia.³ Tangri said his team wanted to test the approach in a higher-risk population.

ReDACKD randomized adults at 2 centers, in Winnipeg and Halifax, Canada. Participants had an estimated glomerular filtration rate (eGFR) of 15–40 mL/min/1.73 m², 2 consecutive serum bicarbonate measurements of 14–22 mEq/L, and serum potassium < 5.3 mmol/L.¹ They received either weekly fruit and vegetable deliveries or oral sodium bicarbonate, which started at 1500 mg daily per the trial protocol.¹,²

Feasibility outcomes were recruitment rate, eligibility, and retention. Secondary outcomes included quality of life, physical function, blood pressure, and biochemical markers.¹

Sodium Bicarbonate Raised Serum Bicarbonate More, but Not Significantly

Of 56 participants assessed, 36 were randomized, 18 to each arm. Follow-up outcome data were available for 91.7% of participants. Completion was lower in the produce arm, where 13 of 18 participants finished the 12-month intervention, compared with 16 of 18 in the sodium bicarbonate arm.¹

Mean serum bicarbonate rose from 19.6 to 19.9 mEq/L with produce delivery and from 20.1 to 21.5 mEq/L with sodium bicarbonate. The adjusted between-group difference was −1.26 mEq/L (95% CI, −3.34 to 0.82; 

 = .23). Blood pressure, eGFR, serum potassium, hemoglobin A1c, and urine albumin-to-creatinine ratio did not differ significantly between groups.¹

Both groups’ mean bicarbonate remained below 22 mEq/L, the upper bound used for trial eligibility. With 36 participants, the trial was not designed to detect efficacy differences, and the confidence interval around the bicarbonate comparison was wide.

Investigators concluded that fruit and vegetable delivery is a feasible way to treat metabolic acidosis in CKD.¹ Tangri said the findings will likely form the foundation of a larger trial. He added that the delivery model could inform research in cardiovascular-kidney-metabolic (CKM) health, such as for patients who return to old eating patterns after a myocardial infarction or heart failure hospitalization.

Editors’ Note: Disclosures for Navdeep Tangri, MD, include AstraZeneca, Bayer, Boehringer Ingelheim, ClinPredict, Eli Lilly and Company, GSK, Janssen Pharmaceuticals, Klinrisk, Marizyme, Mesentech, Otsuka Pharmaceutical, ProKidney, PulseData, Quanta, Renibus Therapeutics, Roche, Tricida, and Vera.

Tangri N, Collister DTB, Balshaw R, et al. Reducing dietary acid with fruits and vegetables vs. oral alkali in people with CKD (ReDACKD): a randomized controlled feasibility trial. Abstract presented at: American Society of Nephrology Kidney Week 2026; October 22–25, 2026; Denver, CO. Abstract TH-PO1248. doi:10.1681/ASN.2026j3pzr03c

Mollard R, Cachero K, Luhovyy B, et al. Reducing dietary acid with fruit and vegetables versus oral alkali in people with chronic kidney disease (ReDACKD): a clinical research protocol. 

. 2023;10:20543581231190180. doi:10.1177/20543581231190180

Goraya N, Simoni J, Jo CH, Wesson DE. A comparison of treating metabolic acidosis in CKD stage 4 hypertensive kidney disease with fruits and vegetables or sodium bicarbonate. 

. 2013;8(3):371-381. doi:10.2215/CJN.02430312

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Serum bicarbonate did not differ significantly between weekly produce delivery and sodium bicarbonate in a 12-month CKD trial.

Urinary potassium excretion rose on a liberalized produce diet, while serum potassium did not differ significantly compared with a restricted diet.

 are often advised to limit potassium-rich fruits and vegetables. In a randomized crossover trial, increasing potassium intake through these foods did not produce a statistically significant increase in serum potassium compared with a restricted diet.¹

Does CKD Require Restricting Potassium-Rich Foods? With Navdeep Tangri, MD

Navdeep Tangri, MD, professor of medicine at the University of Manitoba in Canada, presented the findings at the 

 in Denver, Colorado. In an interview with 

, he highlighted the disconnect between dietary potassium intake, urinary potassium excretion, and blood potassium concentrations.

“I think all of us, when we go back to our physiology textbooks, know that most potassium in the body is not in the blood; it’s inside cells,” Tangri said. “And this goes to show that the link between what you eat, particularly dietary potassium from fruits and vegetables, and what you see in the blood is not as strong as we perhaps think it is.”

Serum Potassium Did Not Differ Significantly Between Diets

The open-label trial randomized 30 adults in Winnipeg, Canada, with an estimated glomerular filtration rate (eGFR) of 15–45 mL/min/1.73 m² and serum potassium concentrations of 4.5–5.5 mEq/L.¹

Because dietary interventions depend on what participants actually eat, investigators delivered groceries to their homes each week. High-potassium produce supported a liberalized intervention targeting 2000 mg/day of potassium from fruits and vegetables, while low-potassium produce supported a standard intervention targeting 500 mg/day.

After a 2-week liberalized run-in, participants completed 6 weeks on each intervention in randomized order, separated by a 2-week washout.¹

Serum potassium, the primary outcome, did not differ significantly between diets (mean difference, −0.014 mEq/L; 95% CI, −0.199 to 0.171; 

Urinary potassium excretion was significantly greater during the liberalized intervention (mean difference, 15.464; 95% CI, 7.606–23.323; 

 < .001), consistent with increased potassium consumption. The ASN abstract did not specify the unit for this difference. Quality of life, physical function, blood pressure, and other biochemical outcomes also showed no statistically significant differences.¹

“I think the most notable thing that stood out to me was the big change in urinary potassium, but very little change in the blood potassium,” Tangri said.

Why Potassium Restriction Advice Persists in CKD

Hyperkalemia occurs in approximately 10% of individuals with CKD and is associated with increased all-cause mortality.² Concerns about elevated serum potassium have contributed to longstanding recommendations to restrict potassium-rich foods, although the evidence supporting broad dietary restrictions has been limited.²

Tangri said these recommendations can leave patients fearful of consuming potassium, even when their serum potassium concentrations are normal.

He described how patients searching for kidney-friendly diets may encounter advice emphasizing potassium restriction before receiving individualized nutritional guidance. In his view, this can discourage the consumption of fruits and vegetables that otherwise contribute to cardiovascular and kidney health.

The randomized crossover trial was designed to test whether increasing potassium specifically through fruits and vegetables would meaningfully affect serum potassium in patients with reduced kidney function.

Which Patients With CKD the Findings Apply To

Tangri suggested that restricting potassium from fruits and vegetables may be unnecessary for many patients with CKD, although he acknowledged that dietary management must account for individual hyperkalemia risk.

The trial was small and short, with only 30 randomized participants and 6 weeks of exposure to each intervention. Participants also had serum potassium concentrations of 5.5 mEq/L or lower at enrollment. These findings therefore cannot establish the long-term safety of dietary liberalization or its applicability to all patients with CKD.¹

Hyperkalemia events were reported. Two participants developed hyperkalemia during the run-in period, and 1 event occurred during the liberalized intervention compared with none during the standard intervention. Two participants did not complete the final visit, including 1 following sudden cardiac death and 1 because of hyperkalemia. The abstract did not establish whether these events were related to the intervention.¹

Tangri also distinguished potassium naturally present in fruits and vegetables from potassium additives in processed foods, noting that the source of dietary potassium may influence its effects.

He suggested that the potential blood pressure and cardiovascular benefits of fruits and vegetables should be considered alongside hyperkalemia risk when counseling patients.

Although the study did not demonstrate that liberalized and restricted diets are equivalent, its findings raise questions about whether blanket restrictions on potassium-rich produce are necessary for appropriately selected patients with CKD.

Editor's Note: Disclosures for Navdeep Tangri, MD, include AstraZeneca, Bayer, Boehringer Ingelheim, ClinPredict, Eli Lilly and Company, GSK, Janssen Pharmaceuticals, Klinrisk, Marizyme, Mesentech, Otsuka Pharmaceutical, ProKidney, PulseData, Quanta, Renibus Therapeutics, Roche, Tricida, and Vera.

Tangri N, Seniuk B, Hager D, et al. Dietary potassium liberalization with fruits and vegetables in people with CKD: a randomized crossover clinical trial. Abstract presented at: American Society of Nephrology Kidney Week 2026; October 22-25, 2026; Denver, CO. Abstract TH-PO1247. doi:10.1681/ASN.2026t1yq1btf

Iman Y, Balshaw R, Alexiuk M, et al. Dietary potassium liberalization with fruit and vegetables versus potassium restriction in people with chronic kidney disease (DK-Lib CKD): a clinical trial protocol. 

. 2023;24(1):301. doi:10.1186/s12882-023-03354-4

In a randomized crossover trial, a liberalized produce diet raised urinary potassium excretion without changing serum potassium.

Navdeep Tangri, MD

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