Vegetarian diet could help men with prostate cancer

Close up shot of a handsome young happy Caucasian man tasting sauce with a mixing spoon with his eyes closed over a frying pan in a kitchen.
Getting more plants into your diet can bring a huge number of health benefits. (Getty Images)

Men with prostate cancer stand to benefit from switching to a vegetarian diet to ease some of their symptoms, a new study has suggested.

Eating a diet rich in fruits, vegetables, grains and nuts, but low in meat and dairy, was linked to fewer issues with erectile dysfunction, urinary incontinence and other symptoms.

Researchers from New York University Grossman School of Medicine and Harvard TH Chan School of Public Health analysed more than 3,500 men with prostate cancer to determine whether a more plant-based diet could improve problems that arise after treatment for the disease.

Prostate cancer is the most common cancer in men, with more than 52,000 UK men diagnosed with it every year on average. According to Prostate Cancer UK, this is equivalent to 144 men every day.

The NHS says the condition does not usually cause symptoms until the cancer has grown large enough to put pressure on the urethra, which can then lead to needing to pee more frequently and difficulty peeing.

But treatments for prostate cancer, like radiotherapy and hormone therapy, can lead to side effects like bladder inflammation that causes problems with peeing, tiredness and weakness, and difficulty getting and maintaining an erection.

Prostate disease and treatment. Male reproductive system anatomical model in doctors hands close-up during consultation of male patient with suspected bacterial prostatitis�
Prostate cancer is the most common cancer in men. (Getty Images)

The latest study, published in the journal Cancer, examined the link between diet and quality of life as a result of these side effects, and found that the group of men who consumed the most plants had better scores in measures of sexual function compared with the group that consumed the least.

Men who ate the most plants scored 8% to 11% higher compared to those who ate the least in this area. Similar results were found for urinary health, with the group eating the most plants scoring up to 14% higher than those who ate the least.

The former group experienced fewer instances of incontinence, obstruction and irritation in relation to their urinary health.

Additionally, men who ate the most plants scored up to 13% better in hormonal health, which included symptoms like low energy, depression, and hot flashes.

Urologist Stacy Loeb, MD, lead author of the study, said: "Our findings offer hope for those looking for ways to improve their quality of life after undergoing surgery, radiation, and other common therapies for prostate cancer, which can cause significant side effects.

"Adding more fruits and vegetables to their diet, while reducing meat and dairy, is a simple step that patients can take."

Previous studies have suggested that a plant-based or vegetarian diet could lower the risk for certain cancers. A 2022 review of 32 studies found that it has the potential to improve prostate cancer outcomes.

High angle view of a large assortment of healthy fresh rainbow colored organic fruits and vegetables. The composition includes cabbage, carrots, onion, tomatoes, raw potato, avocado, asparagus, eggplant, celery, cucumber, broccoli, squash, lettuce, spinach, lemon, apples, pear, strawberries, papaya, mango, banana, grape fruit, oranges, kiwi fruit among others. The composition is at the left of an horizontal frame leaving useful copy space for text and/or logo at the right. High resolution 42Mp studio digital capture taken with SONY A7rII and Zeiss Batis 40mm F2.0 CF lens
Following prostate cancer treatment, eating a diet rich in fruit, vegetables, grains and nuts could help ease side effects, the study suggests. (Getty Images)

Of the studies, a third were observational, which means they relied on information in databases and health registries, while the rest were interventional and involved prostate cancer patients who were observed over time.

Most of the observational studies showed that people who ate plant-based diets developed prostate cancer at lower rates compared to those who ate meat. In more than half of the interventional studies, researchers found that the levels of a prostate-specific antigen (PSA) rose more slowly in plant-eaters.

The rise in PSA levels suggests the cancer is getting worse or recurring. The reviewers pointed towards the slower rise in PSA among plant-eaters, as well as better overall health and a delay in the need for further treatment, as support for the conclusion that vegetarian diets can be beneficial.

However, Dr Stephen Freedland, urologist and director of the Centre for Integrated Research in Cancer and Lifestyle at Cedars-Sinai Medical Centre, cautioned that large-scale clinical trials need to be carried out to confirm the link.

Dr Loeb said the results from her study "add to the long list of health and environmental benefits of eating more plants and fewer animal products".

"They also clearly challenge the historical misconception that eating meat boosts sexual function in men, when in fact the opposite seems to be true."

She cautioned, however, that most of the men assessed were white healthcare professionals, and said the team plans to expand the research to a more diverse group of patients.

Watch: King diagnosed with cancer, Palace announces

Read more about cancer: