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Slowing Prostate Cancer Progression with a Healthy Diet


Research shows that men with early-stage prostate cancer may benefit from a balanced diet.

A healthy diet may help prevent low-risk prostate cancer from progressing more aggressively during active surveillance, a study from the Johns Hopkins University (JHU) School of Medicine finds. Active surveillance is when doctors carefully monitor the growth of a tumor and is an alternative to treatment that could have adverse effects.

The diet was based on the U.S. Department of Agriculture (USDA) Dietary Guidelines for Americans. The balanced eating plan includes fruits, vegetables, grains, dairy, and plant and animal protein sources.
“Many men diagnosed with low grade prostate cancer are interested in changes they can make to reduce the risk of their tumor becoming more aggressive, and the role of diet and nutrition is one of the most commonly asked questions,” study co-senior author Bruce Trock, a professor of urology, epidemiology and oncology at JHU and director of the Brady Urological Institute’s epidemiology division, said in a press release.

“These men are motivated to make changes that may improve their prognosis, which is why we began collecting data on their diets, lifestyles and exposures 20 years ago,” he added.

Diet appears to be one of the factors that can either increase or decrease the risk and progression of prostate cancer. In contrast to the current study associating a healthy diet with prostate cancer protection, some studies link the Western diet to prostate cancer risk.

Active Surveillance

According to the press release, when a biopsy indicates that a man has prostate cancer, it is assigned a Grade Group based on how the cells look compared to noncancerous prostate cells. The Grade Group designations range from 1 to 5, with Grade Group 1 indicating cells that look mildly different from normal and do not spread to other parts of the body. At the top of the scale, Grade Group 5 denotes cells with a highly abnormal appearance that can spread if untreated.

Below is the prostate cancer rating system by the International Society of Urological Pathology.

The Gleason score is the older classification system, but many hospitals report both Grade Groups and Gleason scores. The Gleason score is based on a tissue sample of the prostate, with lower numbers meaning the cancer is less aggressive and less likely to spread.

During active surveillance, a doctor regularly performs biopsies to watch for changes that would reclassify the cancer at a higher grade. If reclassification is necessary, it frequently leads to treatment recommendations.

Healthy Diet Lowered Cancer Risk Scores

The recent study, published in JAMA Oncology in October, followed 886 men with Grade Group 1 prostate cancer. All the men were diagnosed between 2005 and 2017 and were enrolled in the institution’s active surveillance program. Their average age was 66.

At enrollment, the men completed a food frequency questionnaire, which the researchers used to calculate a healthy eating index (HEI) score. This measures how much a person’s diet adheres to the Dietary Guidelines for Americans.

To determine correlations, the researchers reassessed the men 6.5 years after diagnosis.

The researchers found that the healthier the diet, the lower the risk of cancer progression to a higher grade requiring treatment. According to senior author Dr. Christian Pavlovich, a professor in urologic oncology at the JHU School of Medicine and director of the Brady Urological Institute’s prostate cancer active surveillance program, each increase of 12.5 points in the HEI score was associated with a roughly 15 percent decrease in reclassification to Grade Group 2 and a 30 percent decrease in reclassification to Grade Group 3 or higher. Grade Groups 2 and 3 indicate that the prostate cancer poses an intermediate risk compared to Grade Group 1’s low or very low risk.

“The results highlight powerful strategies and reasons to rethink some of our standard nutritional advice in oncology,” Dr. Sandeep Nayak, general and oncology surgeon at Fortis Hospital in Bangalore, India, and medical head at digital health care platform ClinicSpots, told The Epoch Times in an email. “In my view, they have the potential to fundamentally reshape how we integrate dietary guidance into cancer care.”

A Surprising Finding

In addition to the HEI scores, the researchers assessed the inflammatory potential of the men’s diets.

“We hypothesized before conducting the study that inflammation would be associated with progression to a higher grade (more aggressive disease),” Trock told The Epoch Times in an email. “We know that inflammation plays an important role in the development of cancer.”

However, the researchers found a lack of association between inflammation and prostate cancer progression. This was surprising because some studies have found that men who develop prostate cancer have a more inflammatory diet than men who don’t, he continued.

Inflammation doesn’t act in isolation, Trock explained. Diet can influence an array of other important mechanisms, such as immune function, intestinal microbiome, and activation of specific genes. The HEI likely captures many other effects of the diet independent of inflammation.

“One possible explanation for the lack of association is that inflammation plays a greater role in the initial transformation from a healthy prostate to one that has cancer,” he said.

“This is a major biological change involving many steps and circumventing many of the body’s inherent protective mechanisms. In contrast, the change from a Grade Group 1 prostate cancer—which tends to be nonaggressive—to a Grade Group 2 or higher cancer is a much more subtle biological change that may be less influenced by inflammation than other mechanisms,” he added.

Why the Diet Worked

If inflammation doesn’t play a key role in prostate cancer progression, what does? According to Nayak, the Johns Hopkins study indicates that some foods address the specific adverse physiology of cancer.

DNA Repair

“A healthy diet may actually have an active function in the repair of cells. For instance, foods with polyphenols activate DNA repair pathways,” Nayak said. Foods rich in polyphenols include berries, vegetables, nuts, herbs, and spices.

“In other words, this direct support to damaged cells may slow down the multiplication of cancerous cells, thereby providing more value to active-surveillance patients than a simple word on dieting,” he explained.

In his view, these nutrient-specific effects make a diet high in polyphenols an area of possible interest for patients with low-grade prostate cancer.

Hormone Regulation

There is a link between nutrient intake and hormonal factors associated with prostate cancer, said Nayak.

“Vegetables belonging to a cruciferous group, as well as dark leafy green vegetables, contain the compound sulforaphane, which has been found to lower the expression of androgen (male sex hormone) receptors,” he said.

He added that prostate tumors are one of the types of cancer directly dependent on these hormones for growth, so foods containing sulforaphane are a valuable weapon. When taken along with other healthy dietary components, sulforaphane foods can support certain treatments, including hormone therapy, by possibly reducing the cancer’s dependency on androgens.

USDA Diet Versus Western Diet

The USDA Dietary Guidelines for Americans uses a feature called MyPlate to portray healthy eating. It consists of the following:

  • Fruits and Vegetables: These foods should take up half of your plate. Focus on whole fruits and vary vegetables to include different colors and types.
  • Grains: This should take up a little over one-fourth of your plate. At least half of your grains should come from whole grains, such as brown rice, oats, and 100 percent whole-wheat bread.
  • Proteins: This should take up less than one-fourth of the plate. It can include legumes, nuts, seeds, eggs, poultry, meat, and seafood. Poultry and meat should be lean.
  • Dairy: This is an additional group the USDA includes beside the plate, which includes milk, cheese, and yogurt.

Instead of the Dietary Guidelines for Americans, many Americans follow the Western diet, which a review published in the journal Life lists as one of the risk factors for prostate cancer. It involves a high content of fat, calories, sugar, and foods that promote inflammation, such as processed foods. Additionally, it consists of more meat and less fruits and vegetables.

The below chart shows some of the primary differences between the two diets:



An Oncologist Weighs In

Dr. Francisco Contreras, chief oncologist at Oasis of Hope Hospital in Tijuana, Mexico, applauds the study findings because he believes in the power of a healthy diet to fight cancer, he told The Epoch Times via email.

“In the Dietary Guidelines for Americans, there are certain dietary recommendations that have proven to be effective in the risk reduction for prostate and other cancers,” he said.

“Yet there is a plethora of publications in the scientific journals that have been trying, with very little success, to convince and entice medical doctors to prescribe dietary measures to their patients,” he added.

Contreras referred to the Johns Hopkins study as research that, for the first time, indicated a dietary protocol could help keep low-grade prostate cancer patients from progressing to more dangerous states during active surveillance. He hopes similar studies will follow so patients of all malignancies will be encouraged to change their diets to improve prognosis and longevity with a good quality of life.

“At our facility, we have been promoting a similar diet for over 60 years to our patients,” said Contreras.

This diet includes a high intake of fruits and vegetables, particularly those containing lycopene, an antioxidant in tomatoes that has been associated with reduced prostate cancer risk. The diet also involves whole grains, legumes, and healthy fats, such as those found in nuts, seeds, and avocadoes.

Additionally, Contreras advises reducing the intake of red and processed meats, refined carbohydrates,



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