Researchers are examining how the gut may play a powerful supporting role in how prostate cancer develops and progresses. Emerging data show that the trillions of bacteria living in the digestive tract influence inflammation, immune response, and metabolic health throughout the body. This growing area of research, often referred to as the gut–prostate axis, is changing how scientists think about prostate cancer management.

What is gut health?

Gut health refers to the balance and function of the microorganisms that live in the digestive system, known collectively as the gut microbiome. These microbes help break down food, produce essential compounds, regulate inflammation, and help support nearly all parts of the body, including immunity.

The connection between prostate cancer and gut health

Researchers believe the gut–prostate axis influences prostate cancer in several interconnected ways:

• Inflammation: An unhealthy gut may promote chronic, low-grade inflammation that supports tumor growth.
• Oxidative stress: Imbalances in gut bacteria can increase cellular damage.
• Immune surveillance: A healthy microbiome helps the immune system better recognize and respond to cancer cells.

A closer look at the data

A recent clinical trial investigated whether combining phytochemical-rich foods with probiotics and vitamin D could enhance prostate cancer outcomes. The study followed 212 men with PSA-progressing but otherwise indolent prostate cancer who were being managed with active surveillance. 

All participants received a phytochemical-rich supplement made from standardized extracts of ginger, cranberry, pomegranate, turmeric, broccoli, and green tea. Half were also given a probiotic blend containing five Lactobacillus strains, along with prebiotic fiber (inulin) and vitamin D, while the other half received a placebo.

After 16 weeks, the results were encouraging. Men who took the phytochemical supplement alone experienced a meaningful slowing in how quickly their PSA levels were rising. Those who also received probiotics and vitamin D saw an even greater benefit, with PSA levels decreasing on average rather than continuing to rise. The difference between the two groups was statistically significant, suggesting that directly supporting gut health may amplify the effects of a plant-rich diet.

The benefits extended beyond PSA. Men in the probiotic group reported improvements in both urinary symptoms and erectile function compared with those taking the phytochemical supplement alone. Side effects were minimal, with mild bloating reported in a small percentage of participants and no changes in testosterone levels. MRI results were also reassuring, with most men showing stable or improved disease, supporting the idea that PSA changes reflected real biological effects.

What does this mean for you?

For men living with prostate cancer, especially those on active surveillance, this research reinforces the idea that gut health is an important part of overall wellness. While diet and supplements aren’t a substitute for medical care, they may play a meaningful role in reducing inflammation, supporting immune function, and potentially slowing disease progression. 

As scientists continue to study the gut–prostate axis, these findings offer a hopeful reminder that everyday lifestyle choices, including what we eat and how we support our gut, may help shape the prostate cancer journey in powerful ways.

Remember that you can always reach out to an oncology nurse practitioner at Outcomes4Me to help you better understand your diagnosis.