Let’s turn to the venerable Mayo Clinic’s suggestions on lowering your risk of getting prostate cancer (PCa). According to their web article, “Prostate cancer prevention: ways to lower your risk”:
You might consider increasing the amount of fruits and vegetables you eat each day by adding an additional serving of a fruit or vegetable to each meal. Consider eating fruits and vegetables for snacks. … Fruits and vegetables are full of vitamins and nutrients that are thought to reduce the risk of prostate cancer, though research hasn’t proved that any particular nutrient is guaranteed to reduce your risk.i
I have written quite a bit on the relationship between diet and PCa. Some of my blogs have focused on specific fruits, vegetables, nuts, spices and supplements for which there is published evidence of an anti-cancer effect. Some of the evidence is based on lab studies (e.g. exposing cancer cells to a molecular compound in turmeric) while other information comes from human or animal studies. Although none of the data is conclusive, most of it points to the role of eating nutritious foods that have the potential to boost the immune system and deter the destructiveness of cancer cells. There is also an indirect way in which a healthy diet that maintains low weight discourages PCa formation. Weight gain, especially belly fat, promotes dysfunctional metabolic changes and inflammation in the body. Inflammation is a known precursor for developing cancer, including PCa. So, here are two ways in which adding more vegetables and/or fruits and cutting out sugars and refined foods theoretically prevent cancer from starting:
- The molecular compounds in veggies and fruits (vitamins, antioxidants, etc.) may protect against cancer formation, and
- Shedding fat—or not getting fat if you’re already normal weight and BMI—keeps inflammation at bay.
- The intervention group received a counseling behavioral intervention phone promoting consumption of 7 or more daily vegetable servings, especially tomatoes and carrots which are high in carotenoids. At 12 and 24 months there were increases in the amount of vegetables to 9 servings per day.
- A matched control group that got written information about diet and PCa but no other intervention.
Thus, I am a firm believer that increasing vegetable and fruit intake along with other positive health measures is an investment in preventing PCa.
What if you already have prostate cancer?
This brings us to an interesting question: What if prostate cancer is already there? Will improving nutrition, exercise, etc. keep it from getting worse, or maybe even make it go away? To explore that possibility, a randomized Phase III study called the Men’s Eating and Living (MEAL Study) began recruiting in January 2011. The purpose was to determine if diet could alter disease progression (PCa growing and/or becoming more aggressive) among men on Active Surveillance. The study enrolled 478 patients, of whom 443 were eligible; inclusion criteria were biopsy-proven PCa, ages 50-80, PSA < 10, Gleason grade group 1 (or for those > age 70, up to grade group 1), and stage cT2a or less. Participants were each followed for 2 years, while being tracked for progression, carotenoid blood levels, and fat.
The enrollees were randomly assigned into one of two groups:
The good news is, the study showed that men with PCa can sustainably eat healthier diets. Many other studies have proven that eating more veggies, fruits, whole grains and less red or fatty meats offers the benefits of better cardiovascular health, less risk of diabetes, more energy, better sleep, etc.
The bad news is, there was no difference in progression rates (out of 245 cases of progression, 124 were in the intervention group, 121 were in the control group.ii The authors concluded, “The findings do not support use of this intervention to decrease prostate cancer progression in this population…”
To sum up, while many studies support dietary health as a potential way to reduce the risk of developing PCa, once the disease has begun it does not appear that eating more vegetables and fruits has any impact on whether or not it can progress. Two things to keep in mind:
- the authors themselves point out that due to the relatively small number of participants, and the lack of long-term follow-up, it may not have been possible to identify if diet might yet make a difference.
- More importantly, dietary change is an investment in overall health. Healthy men who are diagnosed with PCa tend to have better long-term outcomes than unhealthy men (diabetics, obese men, those with compromised cardiovascular function, etc.).
In short, there is really no excuse for shortchanging yourself when it comes to healthy eating. You are most likely to be your best self, and feel best about yourself and your relationships, when you not only look healthy but ARE healthy. So, whether you’re at risk for PCa or not, it’s never too late to reach for those tomatoes, carrots, cruciferous vegetables like broccoli and cauliflower, and eat up!
iMayo Clinic Staff, “Prostate cancer prevention: ways to reduce your risk.” Mayo Clinic, no date. https://www.mayoclinic.org/diseases-conditions/prostate-cancer/in-depth/prostate-cancer-prevention/art-20045641
iiParsons JK, Zahrieh D, Mohler JL, Paskett E et al. Effect of a Behavioral Intervention to Increase Vegetable Consumption on Cancer Progression Among Men With Early-Stage Prostate Cancer: The MEAL Randomized Clinical Trial. JAMA. 2020 Jan 14;323(2):140-148.