Bananas and Prostate Cancer: Can the Fruit Help Prevent It?

Report: More Research May Be Needed To Support Claims About Prostate Supplements

CINCINNATI (WKRC) - Several supplements are promoted for prostate health but a new report shows more research may be needed to support those claims.

The supplements likely can be found in any pharmacy, but before taking them have a discussion with a health care provider and a pharmacist. A health care provider can make sure the symptoms to be prevented or treated with over-the-counter supplements are not masking a serious health condition, such as prostate cancer.

"We believe that screening for prostate cancer really should be an individualized decision between the patient and their primary care provider. That's where screening really should start," said. Dr. Timothy Struve, a radiation oncologist at UC Cancer Center.

That screening usually involves a blood test for PSA.

"PSA is a protein, and it's excreted by the prostate. In fact, normal prostate produces PSA, but prostate cancer produces PSA at a higher number. So, when the PSA is an abnormal range, that's often a first sign of prostate cancer," Dr. Struve said.

However, for those interested in supplements for prostate health – according to a summary from the Tufts University School of Nutrition Science and Policy, buyer beware.

The summary reviewed research on supplements from a substance in tomatoes called lycopene, soybeans and the isoflavone compounds in them, dairy nutrients in supplements such as calcium and vitamin D, as well as the nut nutrient vitamin E and the Brazil nut nutrient selenium.

Researchers found the most recent information shows lycopene in the diet is good, but there's no recommendation for supplements based on research. They found no benefits to prostate health for calcium and vitamin D supplements. Also, based on the SELECT trial, vitamin E and selenium may increase prostate cancer risk in some men.

The 2024 ZERO Prostate Cancer Run/Walk is Saturday, June 1 at Voice of America Park – UC Health Field House. Those who are interested can attend in person or through a virtual option. Click here to register.

Regular Consumption Of Colorful Fruits And Vegetables Could Help Prevent Prostate Cancer

Men who consume colourful fruits and vegetables on a regular basis are less likely to be diagnosed with prostate cancer (PC), according to new research by University of South Australia scientists.

A rainbow of foods rich in certain micronutrients helps to prevent prostate cancer (PC) as well as speed up recovery among men who undergo radiation treatment for the disease. 

The findings, from two studies published in the journal Cancers, highlight the importance of a Mediterranean or Asian diet that includes these foods.

Researchers compared micronutrient plasma concentrations of prostate cancer patients with a healthy control group, revealing low levels of lutein, lycopene, alpha-carotene, and selenium in PC patients and high levels of iron, sulphur, and calcium in the same group, relative to controls.

Increased DNA damage after radiation exposure was also associated with low lycopene and selenium in blood plasma.

Men with plasma concentrations lower than 0.25 micrograms (ug) per millilitre (mL) for lycopene and/or lower than 120ug/L for selenium have an increased risk of prostate cancer and are likely to be more sensitive to the damaging effects of radiation.

Foods that are rich in lycopene include tomatoes, melons, papayas, grapes, peaches, watermelons, and cranberries. Selenium-rich foods include white meat, fish, shellfish, eggs, and nuts.

Study co-author  Dr Permal Deo says eating foods that are naturally rich in lycopene and selenium is preferable to taking supplements, where the benefits are limited, according to previous studies.

Our recommendation is to adopt a Mediterranean diet enlisting the help of a dietician because people absorb nutrients in different ways, depending on the food, the digestive system, the person's genotype and possibly their microbiome."

Dr Permal Deo, Co-Author  

Prostate cancer remains one of the most common and fatal cancers in men, but the nutritional deficiencies associated with it remain largely unknown, hence this study.

Other risk factors, such as ethnicity, family history and age have previously been linked to prostate cancer.

"There is strong evidence that being overweight and tall increases the risk of prostate cancer. Diets high in dairy products and low in vitamin E may also increase the risk but the evidence is less clear."

Vitamin E is found in plant-based oils, nuts, seeds, fruits, and vegetables.

The research is the first to evaluate plasma concentrations of micronutrients and trace elements with respect to prostate cancer in the South Australian population.

Source:

Journal reference:

Dhillon, V.S., et al. (2023) Plasma Micronutrient Profile of Prostate Cancer Cases Is Altered Relative to Healthy Controls—Results of a Pilot Study in South Australia. Cancers. Doi.Org/10.3390/cancers15010077.

Lycopene Does Not Lower PCa Risk

Study also finds that beta carotene may raise likelihood of aggressive prostate cancer

 

For the past 10 years, many clinicians have been advising men to boost the levels of lycopene in their diet because it could lower their risk for prostate cancer or recurrence for the disease. These recommendations were based on studies showing a protective effect between lycopene consumption and prostate cancer. A recently published study casts doubt on that advice.

 

Researchers reported in Cancer Epidemiology, Biomarkers & Prevention (2007;16:962-968) that lycopene does not effectively prevent prostate cancer. In fact, the investigators observed an association between beta carotene, an antioxidant related to lycopene, and an increased risk for aggressive prostate cancer.

 

The study is one of the largest to evaluate the role of blood concentrations of lycopene and other ca-rotenoid antioxidants in preventing prostate cancer. Study data were derived from over 28,000 men enrolled in the Prostate, Lung, Colo-rectal, and Ovarian (PLCO) Cancer Screening Trial, an ongoing, randomized National Cancer Institute trial to evaluate cancer screening methods and to investigate early markers for cancers.

 

"It is disappointing, since lycopene might have offered a simple and in-expensive way to lower prostate cancer risk for men concerned about this common disease," said study investigator Ulrike Peters, PhD, MPH, as-sistant professor at the Fred Hutchinson Cancer Research Center and an assistant professor in the department of Public Health at the University of Washington in Seattle. "Unfortunately, this easy answer just does not work."

 

Much of the previous research had suggested that a diet rich in lycopene protected against prostate cancer. For the past 5-10 years, this has spurred commercial and public interest in the antioxidant. Antioxidants protect against free radicals, highly active atoms and molecules that can damage DNA and other important molecules in cells. Free radical damage increases with age, so the scientific community has harbored suspicion that this damage could increase the risk of prostate cancer, a disease that has been clearly associated with age.

 

In the last couple of years, however, studies of the potentially protective role of lycopene have been contradictory or inconclusive. In a 2006 study, Dr. Peters and her colleagues looked at the dietary intake of more than 25 tomato-based foods, using data from the PLCO trial, and found no overall association between lycopene intake and prostate cancer.

 

In the new study, the researchers followed more than 28,000 men aged 55-74 years with no history of prostate cancer. The men were initially screened with a PSA test and digital rectal examination and then were followed with routine examinations and screenings until first occurrence of prostate cancer, death, or the end of the trial in 2001. At the beginning of the trial, men gave a blood sample and completed a questionnaire related to their health, diet, and lifestyle.

 

The researchers focused on non-Hispanic Caucasian men, as the small number of cases among other ethnic groups are currently too small to draw any conclusions. They found no significant difference between those who had prostate cancer and those who did not in relation to the blood concentration of lycopene. In addition, the researchers found a relationship between an increased risk of aggressive prostate cancer and beta carotene.

 

Dr. Peters said this was an unexpected observation that could have possibly been due to chance, but "beta carotene is already known to increase risk of lung cancer and cardiovascular disease in smokers. While it would be counterproductive to advise people against eating carrots and leafy vegetables, I would say to be cautious about taking beta carotene supplements, particularly at high doses." 

 

Commenting on the new findings, Martha Terris, MD, chief of urology at the Augusta (Ga.) VeteransAffairsMedicalCenter and a professor of urology at the Medical College of Georgia in Augusta, observed: "It may be like the selenium story. A lot of the things we know may be protective of prostate cancer in low levels, such as selenium, at higher doses may actually promote cancer growth."

 

Much remains unknown about the various minerals and micronutrients in the body and how high doses of these compounds are metabolized. Dr. Terris said she usually tells her patients to stick with the recommended daily allotments of any nutritional supplement, and that getting nutrients from food is better than taking them in pill form.

 

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