Researchers looked at whether the DASH diet—a eating plan designed to lower blood pressure—might help people with kidney disease slow down their condition. They reviewed four studies involving over 7,000 patients followed for an average of 5.5 years. The results suggest that people who stuck closely to the DASH diet had better kidney function improvements compared to those who didn’t follow it as well. While the improvements were meaningful, they weren’t quite strong enough to be completely certain. This research suggests the DASH diet could be a helpful tool for managing kidney disease, but more studies are needed to confirm these benefits.

The Quick Take

  • What they studied: Whether eating according to the DASH diet (which focuses on vegetables, fruits, whole grains, and lean proteins while limiting salt and processed foods) could help slow down kidney disease progression
  • Who participated: Over 7,000 people with chronic kidney disease across four different studies, followed for an average of 5.5 years each
  • Key finding: People who closely followed the DASH diet showed about 6.8% improvement in kidney function, while those who didn’t follow it as closely showed only 1.2% improvement. However, this difference wasn’t statistically proven beyond doubt
  • What it means for you: If you have kidney disease, following the DASH diet more closely may help your kidneys work better, but it’s not a guaranteed cure. Talk to your doctor or a kidney specialist before making major diet changes

The Research Details

This was a systematic review and meta-analysis, which means researchers searched through multiple medical databases (PubMed, Scopus, Web of Science, and others) to find all studies about the DASH diet and kidney disease published between 1997 and 2025. They found 174 studies but only four met their strict quality standards for inclusion. All four studies were prospective cohort studies, meaning researchers followed the same people over time and tracked what they ate and how their kidneys changed. The researchers used a special framework called PICO to make sure they were comparing the same things across all studies. They then combined the results from these four studies to see if there was an overall pattern.

By combining results from multiple studies, researchers can see bigger patterns that might not be obvious in just one study. This approach is stronger than looking at individual studies alone because it reduces the chance that one study’s unusual results will mislead us. The long follow-up periods (averaging 5.5 years) are important because kidney disease changes slowly, so we need to track people for years to see real effects.

The main strength of this review is that it looked at multiple studies and combined their results. However, only four studies met the quality standards, which is a small number. All four studies were observational (watching what people naturally did) rather than randomized controlled trials (where researchers assign people to different diets). This means we can’t be completely sure the DASH diet caused the improvements, since people who follow the diet more closely might also do other healthy things. The researchers registered their plan ahead of time (PROSPERO registration), which is a good sign of transparency.

What the Results Show

The main finding was that kidney function improved more in people who followed the DASH diet closely compared to those who didn’t. Specifically, people with high DASH adherence (meaning they followed the diet well) showed a 6.8% improvement in a kidney function measurement called eGFR, while those with low adherence showed only a 1.2% improvement. In practical terms, this means high adherence improved kidney function by about 3.34 units on the eGFR scale, compared to 0.54 units for low adherence. However, when the researchers did statistical tests, these differences weren’t quite strong enough to be considered definitively proven (the p-values were 0.08 and 0.57, meaning there’s still a chance these results happened by random variation). One study also measured protein in the urine (a sign of kidney damage), and found that people following the DASH diet closely had lower protein levels (33.6 mg/g) compared to those who didn’t follow it well (55.6 mg/g), suggesting less kidney damage.

The review found that consistency matters—people who stuck with the DASH diet more closely got better results than those who only followed it sometimes. The studies used different ways to measure how well people followed the diet (some used scores from 0-40, others from 0-4), but all showed the same pattern: better adherence meant better kidney outcomes. The fact that all four studies showed similar results in the same direction (even though they weren’t perfectly statistically significant) suggests the DASH diet probably does help, but the effect might be modest.

This research builds on previous knowledge that the DASH diet helps lower blood pressure and reduce heart disease risk. Since high blood pressure damages kidneys, it makes sense that a diet that lowers blood pressure would also help kidneys. However, this is one of the first systematic reviews specifically looking at whether DASH helps kidney disease patients. The findings are consistent with the idea that controlling blood pressure through diet is beneficial for kidney health, which aligns with current kidney disease treatment guidelines.

The biggest limitation is that only four studies were included, which is a small number for drawing firm conclusions. All four studies were observational, meaning researchers watched what people naturally did rather than randomly assigning them to follow the DASH diet or not—this makes it harder to prove the diet caused the improvements. Different studies measured kidney function differently, which can make combining results tricky. The studies were conducted over different time periods and in different populations, which adds variability. Most importantly, the improvements in kidney function, while meaningful, weren’t statistically significant, meaning we can’t be completely certain they weren’t due to chance. The review didn’t find enough studies to determine if DASH works equally well for all types of kidney disease or all stages of the disease.

The Bottom Line

If you have chronic kidney disease, talk to your doctor or a kidney specialist about whether the DASH diet might be right for you. The DASH diet emphasizes vegetables, fruits, whole grains, lean proteins, low-fat dairy, nuts, and seeds while limiting salt, added sugars, and red meat. Following it closely appears to offer more kidney benefits than following it loosely. However, this recommendation comes with moderate confidence because the studies weren’t perfectly conclusive. Your kidney specialist may need to adjust the DASH diet for your specific situation, since some kidney disease patients need to limit potassium or phosphorus, which are found in some DASH-recommended foods.

This research is most relevant for people with chronic kidney disease who want to slow their disease progression and avoid needing dialysis or a kidney transplant. It may also interest people with high blood pressure and early kidney disease. People with advanced kidney disease (stages 4-5) should definitely consult their doctor before making diet changes, as their restrictions may be different. This research is less relevant for people without kidney disease, though the DASH diet is generally healthy for everyone.

Kidney disease changes slowly, so you shouldn’t expect dramatic improvements quickly. The studies followed people for an average of 5.5 years, and that’s the timeframe over which meaningful improvements were seen. You might notice some changes in blood pressure within weeks or months, but improvements in kidney function take much longer to measure and confirm. Be patient and consistent with diet changes, and have your kidney function checked regularly (usually every 3-6 months) to see if the diet is helping.

Want to Apply This Research?

  • Track your daily DASH diet adherence score by logging servings of vegetables, fruits, whole grains, lean proteins, and low-fat dairy while noting salt intake. Use a simple 0-10 scale daily to rate how well you followed the diet, then review weekly patterns to identify which meals or days are hardest to stick with
  • Start by making one small DASH-friendly change per week: Week 1 add one extra vegetable serving daily, Week 2 swap one sugary drink for water, Week 3 reduce salt by using herbs instead. This gradual approach is easier to maintain than trying to change everything at once, and it helps you identify which changes work best for your lifestyle
  • Set monthly reminders to review your DASH adherence trends and kidney health markers. Work with your healthcare provider to track eGFR and urine protein levels every 3-6 months, then compare these clinical results with your app’s adherence data to see if higher diet consistency correlates with better kidney function in your individual case

This research suggests the DASH diet may help slow kidney disease progression, but the evidence is not yet conclusive. This information is for educational purposes only and should not replace professional medical advice. If you have chronic kidney disease, consult your nephrologist (kidney specialist) or registered dietitian before making significant dietary changes, as your individual kidney condition may require specific restrictions on potassium, phosphorus, sodium, or protein that differ from standard DASH recommendations. Do not use this information to diagnose or treat kidney disease. Always work with your healthcare team to develop a personalized nutrition plan based on your specific kidney function tests and medical history.