Researchers followed over 113,000 people for more than 11 years to see how their eating habits affected their chances of getting kidney cancer. They found that people who ate Mediterranean-style diets, heart-healthy diets, or DASH diets (designed to lower blood pressure) had lower kidney cancer risk. Interestingly, people who ate more inflammatory foods—foods that cause swelling in the body—had higher risk. The study also showed that your genes matter, but eating well can help protect you even if you have genes that increase kidney cancer risk.

The Quick Take

  • What they studied: Whether eating certain types of diets could lower the risk of developing kidney cancer, and how a person’s genes and diet work together to affect this risk.
  • Who participated: Over 113,000 people from the UK Biobank study who provided detailed information about what they ate. Researchers tracked them for an average of 11.4 years to see who developed kidney cancer.
  • Key finding: People who closely followed Mediterranean, heart-healthy, or DASH diets had about 30-33% lower kidney cancer risk. People eating more inflammatory foods had about 36% higher risk. Those with high genetic risk could reduce their risk by eating healthier.
  • What it means for you: Eating Mediterranean, heart-healthy, or DASH-style diets may help reduce kidney cancer risk, especially if you have family history of kidney cancer. However, this study shows association, not proof of cause-and-effect, so talk to your doctor about your personal risk.

The Research Details

This was a prospective cohort study, which means researchers followed real people over time and watched what happened to them. They started with 113,594 people from the UK Biobank who had recorded what they ate using detailed 24-hour food diaries at least twice. The researchers then tracked these people for an average of 11.4 years and recorded who developed kidney cancer during that time.

The researchers measured how closely each person followed four different eating patterns: the Mediterranean diet (lots of vegetables, fish, and olive oil), a heart-healthy diet, the DASH diet (designed to lower blood pressure), and a pro-inflammatory diet (foods that cause swelling in the body). They also looked at each person’s genetic risk using a special genetic test called a polygenic risk score, which combines information from many genes that affect kidney cancer risk.

The researchers used statistical methods to figure out whether diet and genes were connected to kidney cancer risk, while accounting for other factors like age, smoking, exercise, and body weight that could affect the results.

This research approach is important because it follows real people in their everyday lives rather than just studying cells in a lab. By tracking people over more than 11 years, researchers can see which eating patterns are actually connected to lower kidney cancer rates. The study also looked at how genes and diet work together, which is important because some people may need to pay extra attention to diet if they have genetic risk factors.

This study has several strengths: it included over 113,000 people (a large sample size), followed them for over a decade, and used detailed food records rather than just asking people to remember what they ate. The researchers also adjusted their analysis for many other factors that could affect kidney cancer risk. However, the study cannot prove that diet causes lower kidney cancer risk—it only shows that certain diets are connected with lower risk. People who eat healthy diets may also exercise more or have other healthy habits that protect them.

What the Results Show

During the study, 425 people developed kidney cancer. People who scored highest on the Mediterranean diet scale had about 29% lower kidney cancer risk compared to those who scored lowest. People who followed the DASH diet most closely had about 33% lower risk. In contrast, people who ate the most inflammatory foods had about 36% higher kidney cancer risk.

The study also found that genes and diet work together. People with high genetic risk who also ate unhealthy diets (low Mediterranean, low DASH, or high inflammatory) had the highest kidney cancer risk. However, people with high genetic risk who ate healthier diets had much lower risk, showing that diet can help protect you even if you have genes that increase your risk.

The researchers also looked at blood markers like cholesterol, blood sugar, and inflammation levels. These markers appeared to explain some of the connection between diet and kidney cancer risk, though they only explained a small part (less than 9% of the effect).

The heart-healthy diet (AHEI) also showed a protective effect, though the results were slightly less strong than for Mediterranean and DASH diets. The study found that the protective effect of healthy diets was strongest in people with high genetic risk, suggesting that diet matters most for those with family history of kidney cancer. Blood sugar control, cholesterol levels, and inflammation markers all appeared to play some role in how diet affects kidney cancer risk.

This study builds on previous research showing that diet and genes both affect kidney cancer risk. However, this is one of the first large studies to look at how diet and genes work together. Previous studies mostly looked at diet or genes separately. The findings support what other research has shown about Mediterranean and DASH diets being protective for many health conditions, and extend this to kidney cancer specifically.

The study cannot prove that eating these diets causes lower kidney cancer risk—it only shows they are connected. People who eat Mediterranean or DASH diets may also exercise more, not smoke, or have other healthy habits that protect them. The study included mostly people from the UK, so results may not apply equally to other populations. Also, people reported their own food intake, which can be inaccurate. The study only included people who were willing to participate and provide detailed food records, so results may not represent everyone.

The Bottom Line

Based on this research, eating Mediterranean-style, heart-healthy, or DASH diets appears to be associated with lower kidney cancer risk (moderate confidence level). Limiting inflammatory foods appears associated with higher risk (moderate confidence level). These diets are also known to protect against heart disease and diabetes, so they offer multiple health benefits. Talk to your doctor about whether these diets are right for you, especially if you have family history of kidney cancer.

Everyone can benefit from eating healthier diets, but this research is especially relevant for people with family history of kidney cancer, people with genetic risk factors, and people over age 50 (when kidney cancer is more common). People with kidney disease should talk to their doctor before making major diet changes. The findings apply to adults; it’s unclear if they apply to children.

The protective effects of healthy diets likely build up over years, not weeks or months. In this study, people were followed for over 11 years. You may notice other benefits of healthy eating (like more energy, better digestion, or weight loss) within weeks to months, but kidney cancer prevention is a long-term benefit.

Want to Apply This Research?

  • Track daily adherence to Mediterranean or DASH diet components: servings of vegetables (goal: 5+), fish meals per week (goal: 2+), whole grains (goal: 3+ servings), and limit processed/inflammatory foods. Score yourself 0-10 daily based on how well you followed these patterns.
  • Start by adding one Mediterranean or DASH diet element each week: Week 1 add more vegetables, Week 2 add fish, Week 3 switch to whole grains, Week 4 reduce processed foods. Use the app to log meals and get real-time feedback on how well you’re following these patterns.
  • Track weekly diet pattern scores, monthly blood pressure and weight (if available), and quarterly check-ins with your doctor about kidney health. Set reminders for grocery shopping focused on Mediterranean/DASH foods. Review your diet pattern trends monthly to stay motivated.

This research shows associations between diet and kidney cancer risk but does not prove cause-and-effect. Individual kidney cancer risk depends on many factors including genetics, age, smoking, obesity, and medical conditions. This information is for educational purposes and should not replace medical advice from your doctor. If you have concerns about kidney cancer risk or want to make major diet changes, especially if you have kidney disease or take medications, please consult with your healthcare provider before making changes.