Researchers followed nearly 80,000 men from different racial and ethnic backgrounds for almost 19 years to see if eating healthy patterns could lower prostate cancer risk. While they didn’t find strong overall results, they discovered that diet may work differently depending on a man’s race or ethnicity and the type of cancer. For African American men, eating a heart-healthy DASH diet showed promise for reducing aggressive prostate cancer risk. For Japanese American men, a diet linked to better insulin control was connected to lower-risk prostate cancers. These findings suggest that one-size-fits-all dietary advice may not work for everyone when it comes to prostate cancer prevention.

The Quick Take

  • What they studied: Whether eating different types of healthy diets could help prevent prostate cancer or reduce the risk of aggressive forms of the disease
  • Who participated: Nearly 80,000 men aged 45-75 from five different racial and ethnic groups: White, African American, Japanese American, Latino, and Native Hawaiian men living in Hawaii and California
  • Key finding: Overall, healthy eating patterns didn’t strongly prevent prostate cancer across all men studied. However, African American men who followed a heart-healthy DASH diet had about 14% lower risk of advanced prostate cancer, and Japanese American men with diets that help control blood sugar had slightly higher rates of slow-growing prostate cancers
  • What it means for you: Eating healthy is still important for overall health, but the connection between specific diets and prostate cancer prevention may depend on your racial or ethnic background. Talk to your doctor about what dietary choices make sense for your personal health situation rather than following generic cancer-prevention diet advice

The Research Details

This was a long-term follow-up study called a cohort study, where researchers tracked the same group of men over time to see what happened to their health. Scientists looked at what nearly 80,000 men ate using food questionnaires and then followed them for an average of 18.8 years to count how many developed prostate cancer. The researchers examined 11 different healthy eating patterns, including the popular DASH diet (which emphasizes vegetables, fruits, and whole grains) and other patterns designed to reduce disease risk.

The researchers used a statistical method called Cox proportional hazards models to calculate the risk of prostate cancer based on how closely men followed each diet pattern. They looked at the overall group and also separately examined each racial and ethnic group to see if diet affected different populations differently. They also looked at whether diet affected aggressive versus non-aggressive forms of prostate cancer.

This approach matters because previous studies on diet and prostate cancer have given mixed results, and most research has focused on White populations. By studying a large, diverse group of men and following them for nearly two decades, researchers could see if diet recommendations should be different for different groups. Looking at cancer aggressiveness is important because some prostate cancers grow slowly and may never cause harm, while others are dangerous and need treatment.

This study has several strengths: it included a very large number of men (nearly 80,000), followed them for almost 19 years, included diverse racial and ethnic groups, and carefully tracked their diets. However, the study relied on men remembering what they ate, which can be inaccurate. The researchers also tested many different diet patterns, which increases the chance of finding results by accident rather than real effects. The study was observational, meaning researchers watched what happened rather than randomly assigning men to different diets, so we can’t prove that diet caused the differences in cancer risk.

What the Results Show

When looking at all men together, the researchers found no strong connection between any of the 11 healthy eating patterns they studied and prostate cancer risk overall. This was surprising because previous research suggested that healthy diets should reduce cancer risk. The lack of strong overall findings suggests that diet’s effect on prostate cancer may be more complicated than previously thought.

However, when researchers looked at specific racial and ethnic groups separately, they found some interesting patterns. Among African American men, those who followed the DASH diet (which emphasizes vegetables, fruits, whole grains, and low-fat dairy) had about 14% lower risk of advanced prostate cancer. This finding was suggestive but not definitive, meaning it’s worth investigating further but not yet proven.

Among Japanese American men, the results were different. Men whose diets were high in foods that help control blood sugar levels actually had slightly higher rates of low-grade (slow-growing) and non-aggressive prostate cancers. This is interesting because these are typically less dangerous forms of cancer, and the increase was small.

The researchers found no significant associations between diet and prostate cancer in White, Latino, or Native Hawaiian men in this study. The differences between racial and ethnic groups suggest that genetics, lifestyle factors, or how different populations respond to foods may play important roles in prostate cancer risk. The fact that diet affected aggressive cancer differently than non-aggressive cancer in some groups shows that one diet may not prevent all types of prostate cancer equally.

Previous research has suggested that healthy diets reduce cancer risk in general, but studies specifically looking at prostate cancer have given mixed results. Some studies found that Mediterranean-style diets or plant-based diets helped prevent prostate cancer, while others found no benefit. This new study’s findings align with the mixed previous results and add important information by showing that diet’s effects may differ by race and ethnicity. This suggests that past studies, which often focused on single racial groups, may have missed important differences in how diet affects different populations.

The study has several important limitations. First, researchers asked men once or twice about their diet, but people’s eating habits change over time, so this snapshot may not represent their typical diet. Second, the study couldn’t prove that diet caused the differences in cancer risk—other factors like exercise, stress, sleep, or genetics could explain the results. Third, the researchers tested 11 different diet patterns, which means some findings could have occurred by chance. Fourth, some of the findings were only suggestive (not statistically strong), meaning they need confirmation in future studies. Finally, the study included relatively few cases of advanced cancer in some groups, making it harder to draw firm conclusions.

The Bottom Line

Based on this research, general healthy eating recommendations remain important for overall health, but specific diet patterns may affect prostate cancer risk differently depending on your racial or ethnic background. If you’re an African American man concerned about prostate cancer, the DASH diet (rich in vegetables, fruits, whole grains, and low-fat dairy) may offer some protection against aggressive forms. For all men, maintaining a healthy weight, exercising regularly, and eating mostly plant-based foods remain sensible health practices. However, these findings are preliminary and should not replace conversations with your doctor about personalized cancer prevention strategies. Confidence level: Low to moderate—these findings are suggestive but need confirmation in future studies.

These findings are most relevant for men concerned about prostate cancer prevention, particularly African American and Japanese American men. All men should care about prostate cancer prevention, but this research suggests that one universal diet recommendation may not work equally well for everyone. Men with a family history of prostate cancer, men over 50, and African American men (who have higher prostate cancer rates) should discuss personalized prevention strategies with their doctors. This research is less immediately applicable to women, though understanding men’s health is important for families.

If dietary changes do affect prostate cancer risk, the benefits would likely take years to appear, as this study followed men for an average of 18.8 years. Don’t expect to see health benefits from diet changes in weeks or months when it comes to cancer prevention. However, healthy eating provides many other benefits (better heart health, weight management, more energy) that appear much sooner. Focus on sustainable eating habits rather than expecting quick results.

Want to Apply This Research?

  • Track daily servings of vegetables, fruits, whole grains, and low-fat dairy products (key components of the DASH diet) to monitor adherence to heart-healthy eating patterns. Set a goal of 5+ servings of vegetables and fruits daily, 3+ servings of whole grains, and 2-3 servings of low-fat dairy.
  • Start by adding one DASH diet element to your meals each week: Week 1 add more vegetables, Week 2 add whole grains, Week 3 add low-fat dairy. Use the app to log these foods and celebrate small wins. Create meal prep reminders for Sunday to prepare vegetables and whole grains for the week ahead.
  • Track dietary patterns monthly rather than daily to reduce overwhelm. Use the app’s trend feature to see if you’re gradually increasing healthy foods. Set quarterly check-ins with your doctor to discuss overall health and cancer prevention strategies. Monitor how you feel (energy levels, digestion, weight) as motivation for continuing healthy eating habits.

This research provides preliminary evidence about diet and prostate cancer risk and should not be used as a substitute for professional medical advice. The findings are suggestive and require confirmation in future studies. Prostate cancer risk depends on many factors including age, family history, genetics, and race/ethnicity—diet is just one piece of the puzzle. All men, especially those over 50 or with risk factors, should discuss prostate cancer screening and prevention strategies with their healthcare provider. This article is for educational purposes only and does not constitute medical advice. Always consult with your doctor before making significant dietary changes, especially if you have existing health conditions or take medications.