Researchers studied 83 people with early-stage kidney disease to see if eating healthier foods could help their kidneys work better. For one month, patients worked with nutrition experts to eat less processed food and more whole foods, while controlling protein intake. The results were encouraging: people who followed the plan had better kidney function, healthier blood protein levels, and improvements in blood sugar and mineral balance. This suggests that simple changes to what you eat—especially avoiding ultra-processed foods—might help slow kidney disease progression in its early stages.

The Quick Take

  • What they studied: Whether eating better food—specifically avoiding ultra-processed foods and managing protein intake—could improve kidney function and blood chemistry in people with early-stage kidney disease
  • Who participated: 83 adults (average age 62, about half men) with early chronic kidney disease who weren’t yet on dialysis. Most were overweight and had moderately reduced kidney function
  • Key finding: After just one month of working with a nutrition expert to eat better, patients had measurably better kidney function (35% improvement in kidney filtering ability), healthier blood protein levels, and better control of blood sugar and minerals like potassium and sodium
  • What it means for you: If you have early kidney disease, working with a nutrition expert to eat more whole foods and fewer processed foods may help protect your kidneys and improve your overall health. However, this is a short-term study, so longer-term benefits need more research

The Research Details

This was a short-term study where researchers measured what 83 people with early kidney disease ate and their blood chemistry at the start, then again after one month of working with nutrition experts. The nutrition experts helped patients understand how to eat better by reducing ultra-processed foods (like packaged snacks, fast food, and sugary drinks) and eating more whole foods (like fresh fruits, vegetables, and whole grains). They also helped patients manage their protein intake appropriately for their kidney condition.

Researchers used two methods to track what people ate: a detailed 24-hour food recall where patients described everything they ate in one day, and a food frequency questionnaire where they reported how often they ate certain foods. Blood tests measured kidney function, protein levels, potassium, sodium, glucose, and other important markers.

The study compared how much ultra-processed food people ate before and after the intervention, and looked at whether improvements in kidney function and blood chemistry happened in people who followed the nutrition plan well.

This research approach is important because it shows real-world results in actual patients with kidney disease, not just in laboratory settings. By measuring both diet changes and blood chemistry improvements, researchers could see whether eating better actually leads to measurable health benefits. The one-month timeframe, while short, was enough to show that dietary changes can have quick positive effects on kidney function and blood chemistry

This study has some strengths: it measured actual food intake using validated methods, included blood tests to confirm improvements, and showed statistically significant results. However, readers should know that 83 people is a relatively small group, the study only lasted one month (so we don’t know if benefits continue longer), and there was no comparison group eating normally to compare against. The study was also published recently (2025), so it represents current research standards

What the Results Show

The main finding was that after one month of nutritional care, people significantly reduced their intake of ultra-processed foods. The amount of calories coming from ultra-processed foods dropped noticeably, and this change was statistically significant (meaning it wasn’t due to chance).

People who successfully ate adequate protein (as recommended for their kidney condition) showed even better results: they ate less ultra-processed food and more whole, minimally-processed foods compared to those who didn’t meet protein goals. This suggests that following the complete nutrition plan—not just one part of it—works best.

The blood test results were particularly encouraging. Kidney function, measured by how well kidneys filter waste, improved significantly. Blood protein (albumin) levels increased, which is a sign of better nutrition. Importantly, dangerous minerals like potassium and sodium decreased to healthier levels, and blood sugar control improved, with both glucose and glycated hemoglobin (a marker of long-term blood sugar) decreasing.

Beyond the main findings, the study showed that patients who followed the nutrition plan well had coordinated improvements across multiple health markers. This suggests that the benefits weren’t isolated to one area but represented overall better health. The fact that both immediate blood sugar markers and long-term blood sugar control (glycated hemoglobin) improved suggests the dietary changes had meaningful effects on metabolism

This research supports existing evidence that protein management is important in early kidney disease, but adds new information about the specific benefits of reducing ultra-processed foods. Previous studies suggested that ultra-processed foods might harm kidneys, but this is one of the first studies to show that reducing them actually improves kidney function in real patients. The improvements in kidney function and blood chemistry align with what nutrition experts have recommended for years, but now we have evidence that these recommendations actually work in practice

The study only lasted one month, so we don’t know if benefits continue or improve over longer periods. There was no control group of people eating normally to compare against, so we can’t be completely certain the improvements were due to the nutrition intervention rather than other factors. The study included only 83 people, which is relatively small, so results might differ in larger or more diverse populations. The study didn’t track whether people maintained these dietary changes after the month ended. Additionally, all participants were in early kidney disease stages, so results may not apply to people with more advanced kidney disease

The Bottom Line

If you have early-stage kidney disease, working with a nutrition expert to reduce ultra-processed foods and manage protein intake appears to help kidney function and blood chemistry (moderate confidence based on this one-month study). This is especially true if you can achieve adequate protein intake as recommended for your specific kidney stage. These changes should be made under medical supervision, as kidney disease requires personalized nutrition plans

People with early-stage chronic kidney disease (stages 2-3) who aren’t yet on dialysis should pay attention to these findings. This is particularly relevant if you’re overweight or have blood sugar control issues, as the study showed improvements in these areas. However, people with advanced kidney disease (stage 4-5) or those already on dialysis should follow their nephrologist’s specific recommendations, as their nutritional needs differ. Anyone with kidney disease should consult their doctor or a kidney specialist before making major dietary changes

Based on this study, you might expect to see improvements in blood chemistry within one month of making dietary changes. However, this is a short timeframe, and longer-term benefits may take several months to become apparent. Kidney function improvements may continue beyond one month with sustained dietary changes. Individual results will vary based on how well you follow the nutrition plan and your specific kidney disease stage

Want to Apply This Research?

  • Track daily intake of ultra-processed foods versus whole foods using a simple log (e.g., number of servings of processed foods vs. whole foods per day). Set a goal to reduce processed food servings by 50% over one month and monitor weekly progress
  • Use the app to identify and replace one ultra-processed food you eat regularly with a whole food alternative. For example, replace packaged snacks with fresh fruit, or fast food meals with home-prepared meals. Start with one substitution and add more as it becomes routine
  • Set up monthly reminders to log your dietary patterns and any available blood test results (potassium, sodium, glucose, kidney function markers if your doctor orders them). Create a trend chart showing your progress in reducing ultra-processed foods over 3-6 months. Share this data with your healthcare provider to adjust your nutrition plan as needed

This research describes findings from a one-month study in 83 people with early-stage kidney disease. Individual results may vary significantly. If you have kidney disease or any chronic health condition, consult your doctor or a registered dietitian specializing in kidney disease before making major dietary changes. This information is educational and should not replace personalized medical advice from your healthcare provider. Kidney disease requires individualized nutrition plans based on your specific stage and other health conditions. Do not self-treat or delay seeking professional medical care based on this information.