Researchers studied over 205,000 people to understand how different eating patterns affect kidney health, especially in people with heart or diabetes problems. They found that following the American Heart Association’s recommended diet—which emphasizes fruits, vegetables, whole grains, and lean proteins—was the most effective way to prevent kidney disease from developing. People who stuck closely to this diet had about 37% lower risk of developing kidney problems compared to those who didn’t follow it. Interestingly, eating lots of processed plant-based foods was linked to higher kidney disease risk. The study suggests that what you eat matters most for preventing kidney disease before it starts.

The Quick Take

  • What they studied: Whether following different healthy eating guidelines could help prevent kidney disease in people who already have heart problems or diabetes
  • Who participated: Over 205,000 adults from the UK Biobank study who provided detailed information about what they ate and were tracked for kidney health over time
  • Key finding: People who closely followed the American Heart Association diet had 37% lower risk of developing kidney disease compared to those who didn’t follow it. People who ate lots of unhealthy processed plant-based foods had 44% higher risk of kidney disease.
  • What it means for you: If you have heart disease or diabetes, eating more fruits, vegetables, whole grains, and lean proteins (the AHA diet) may help protect your kidneys. However, this study shows association, not proof of cause-and-effect, so talk to your doctor about what diet is right for you.

The Research Details

This was a large observational study that followed real people over time rather than a controlled experiment. Researchers looked at information from 205,826 people in the UK Biobank who reported what they ate using detailed 24-hour food diaries. They then tracked these people to see who developed kidney disease and compared their eating patterns.

The researchers used a special statistical method called multi-state modeling, which is like following a path: starting healthy → developing heart/diabetes problems → developing kidney disease → potentially death. This approach let them see how diet affected movement along this path, rather than just looking at one point in time.

Nine different dietary patterns were studied, including the American Heart Association (AHA) diet, the DASH diet, and others. Researchers calculated how closely each person followed each diet pattern and then looked for connections between diet adherence and kidney disease risk.

This approach is important because kidney disease usually develops in people who already have other health problems like diabetes or heart disease. By studying the actual progression of disease in real people, rather than just looking at snapshots, researchers can better understand which eating patterns truly protect kidneys at different stages of disease.

This study has several strengths: it included a very large number of people (over 205,000), used detailed dietary information from food diaries rather than memory, and followed people over time to see actual health outcomes. However, it’s observational, meaning researchers couldn’t control all factors that might affect results. People who eat healthier may also exercise more or take medications, which could partly explain the benefits. The study was conducted in the UK, so results may differ in other populations.

What the Results Show

The American Heart Association diet showed the strongest protection against kidney disease. People in the highest group of AHA diet adherence had a 37% lower risk of developing kidney disease compared to those in the lowest group. This protective effect was even stronger in people with type 2 diabetes—they had a 17% additional risk reduction for each point increase in their AHA diet score.

In contrast, a plant-based diet high in unhealthy processed foods (like veggie burgers, plant-based meats, and processed snacks) was associated with higher kidney disease risk. People eating the most of these processed plant foods had 44% higher risk compared to those eating the least.

Other dietary patterns like the DASH diet and EAT-Lancet diet showed some protective effects, but they were weaker than the AHA diet. The study found that the AHA diet’s benefits came from its emphasis on whole foods: fruits, vegetables, whole grains, fish, and limited salt and sugar.

Interestingly, once people developed kidney disease, the diet they ate didn’t seem to affect how long they lived. This suggests that diet is most important for preventing kidney disease from developing in the first place, rather than for managing it after it starts. The researchers also found that the protective effects of the AHA diet were most pronounced in people with diabetes, suggesting this group may benefit most from dietary changes.

Previous research has shown that healthy eating patterns protect the heart and help control diabetes. This study extends that knowledge by showing these same patterns also protect the kidneys. The finding that processed plant-based foods increase kidney disease risk is newer and somewhat surprising, as plant-based eating is often promoted as healthy. However, this study specifically looked at processed plant foods, not whole plant foods like beans and nuts, which may have different effects.

This study shows association but cannot prove that diet directly causes the kidney protection observed. People who eat healthier may also exercise more, take medications regularly, or have other healthy habits that contribute to kidney protection. The study was conducted in the UK with mostly white participants, so results may not apply equally to other populations. Additionally, people reported their diet at one point in time, but eating habits may have changed during the study period.

The Bottom Line

If you have heart disease, diabetes, or other cardio-metabolic conditions, consider adopting the American Heart Association diet pattern, which emphasizes: fruits and vegetables (aim for variety and color), whole grains instead of refined grains, lean proteins like fish and poultry, limited salt and added sugars, and healthy fats. Avoid processed plant-based meat and snack products. Confidence level: Moderate—this study shows strong association but isn’t definitive proof. Always consult your doctor before making major dietary changes, especially if you have kidney disease.

This research is most relevant for people with diabetes, heart disease, high blood pressure, or other cardio-metabolic conditions who want to protect their kidney health. It’s also relevant for people with early-stage kidney disease who want to slow progression. People with advanced kidney disease should follow their nephrologist’s specific dietary recommendations, which may differ from general guidelines. Healthy people without these conditions can also benefit from the AHA diet for overall health.

Kidney disease typically develops slowly over months to years. You likely won’t notice immediate changes, but consistent adherence to a healthy diet pattern over 6-12 months may help slow or prevent kidney disease progression. Benefits are most likely to appear over years of consistent eating habits.

Want to Apply This Research?

  • Track adherence to the AHA diet by logging daily servings of: fruits (aim for 2-3), vegetables (aim for 3-4), whole grains (aim for 3-4), lean proteins (aim for 2-3), and sodium intake (aim for under 2,300mg). Rate overall adherence on a 1-10 scale daily.
  • Start by making one simple swap per week: replace white bread with whole wheat, add one extra vegetable to dinner, or swap one processed snack for fruit. Use the app to set reminders for meal planning and grocery shopping focused on whole foods.
  • Weekly check-ins on diet adherence score, monthly reviews of average adherence trends, and quarterly discussions with your doctor about kidney function tests (if applicable). Track any changes in energy levels, blood sugar control, or blood pressure as secondary indicators of diet quality.

This research shows associations between diet and kidney disease risk but does not prove cause-and-effect relationships. Individual results vary based on genetics, medications, and other health factors. If you have kidney disease, diabetes, heart disease, or are taking medications that affect kidney function, consult your doctor or a registered dietitian before making significant dietary changes. This information is not a substitute for professional medical advice. Always work with your healthcare team to develop a personalized nutrition plan appropriate for your specific health conditions.