A new study combined six foods with a probiotic and found ‘significant’ results
A diet rich in vegetables and probiotics could help slow the growth of low-risk prostate cancer, a new study suggests. Researchers found that specially designed supplements and probiotics appeared to slow progression of an indicator of prostate cancer in the blood.
Academics said that the link between the gut and the prostate, known as the “gut-prostate axis”, is increasingly being recognised as they set out to investigate whether increasing the level of “phytochemical-rich foods and Lactobacillus probiotics” would have an effect on prostate cancer.
They developed a supplement made from broccoli, turmeric, pomegranate, green tea, ginger and cranberry and a specially designed probiotic. Some 212 men with low-risk prostate cancer were recruited to the study.
Half the men were given the supplement and a placebo, also known as a dummy drug. The other half were given the supplement and the probiotic. Researchers, led by a team from the University of Bedfordshire along with experts from Cambridge University Hospitals and Bedford Hospital, then measured prostate-specific antigen (PSA) in blood.
The PSA test can indicate prostate conditions including prostate cancer or an enlarged prostate. Working with scientists from California in the US, and Perth in Australia, they found that the rate of PSA progression slowed significantly in both groups of men taking part in the trial.
But the rate of change was “significantly greater” among the group who got the supplement and the probiotic. Meanwhile, researchers also used MRI scans to measure disease progression during the four-month study.
They found among that those who had the supplement and placebo, 82% had “stable disease” while 18% saw their disease progressed. Among those who had the supplement and the probiotic, 85.5% of men had stable disease, 6.7% “exhibited disease regression” and 7.8% saw their disease progress.
Writing in the European Urology Oncology journal, the authors said they found a “significant slowing of progression in PSA” following dietary changes among men with low-risk prostate cancer. They said that their study is also the first to show “additional intervention” of the probiotic “significantly reduced PSA progression as well as serum markers of inflammation further”.
The authors said that the finding is “clinically relevant” because men will often use PSA changes as a factor in indicating whether or not they want to remain having “active surveillance” or whether they have treatment or surgery. “Currently about 60% of men, with lower-risk disease, initially opt for active surveillance, but alarmingly over 50% opt out within five years,” the authors said.
“As fewer than 5% of men in this prognostic group are likely to die from their disease, a successful dietary intervention, which helps men remain on active surveillance, could help avoid treatment-related toxicities in a large majority who might otherwise be over-treated.”
They point out that a quarter of men in the study also reported improvements of urinary symptoms. But they stressed that the study period was only four months so called for longer-term studies to confirm the findings.
“This study adds to the growing evidence that men managed with surveillance can empower themselves through lifestyle changes that could influence prostate cancer progression and improve their symptoms,” the authors conclude. “In addition to modifiable factors such as exercise, smoking, and omega-3–rich diets, this study suggests that boosting dietary phytochemicals and probiotics could also help.”
First author of the study, Professor Robert Thomas, from the University of Bedfordshire and consultant clinical oncologist, said: “This study shows, for the first time, that improving the balance of bacteria in the gut can slow prostate cancer activity while also improving important aspects of men’s health such as urinary symptoms, inflammation and physical strength.
“What is particularly reassuring is that the changes we saw in PSA were supported by changes on MRI scans, which is very unusual and unique in nutritional research. This was a carefully designed clinical trial carried out under medical supervision and, while the results are encouraging, longer follow-up is planned to assess whether these supplements will lead to less men needing major interventions such as surgery or radiotherapy.”
Dr Jeffrey Aldous, senior lecturer in exercise physiology at the University of Bedfordshire, added: “This research helps us understand how targeted dietary strategies may influence the gut microbiome in ways that appear to benefit both cancer-related markers and overall wellbeing.
“Improvements in strength, inflammation and daily symptoms are particularly important for quality of life, and I hope our findings can support and improve the lives of those living with prostate cancer.”
Commenting, Dr Hayley Luxton, head of research impact and engagement at Prostate Cancer UK, said: “This study is encouraging and adds to growing research into how diet and gut health can affect prostate cancer progression. It suggests that healthier diets could lead to better outcomes for some men – all while improving their overall wellbeing.
“At Prostate Cancer UK, we know how important it is to find ways to make treatments both kinder and more effective for those who need them. While more research is needed to say exactly what role probiotics and supplements can play, having a balanced, healthy diet remains a good idea.”
