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The Truth About Prostate Cancer Supplements

November 13, 2014

Prostate cancer is the second most common cancer in the United States. Each year, an estimated 230,000 men are diagnosed with the disease, and about 30,000 will die from it.

It is the most common cancer among men, and that may be why there’s been increased interest in prostate cancer prevention. Many products currently claim to prevent or reduce the risk of developing this cancer, but these claims often lack evidence.

There have been several reports about how a certain diet or prescription therapy can lower cancer risks. Other studies tout the benefits of vitamin E and vitamin D for cancer prevention. With all this conflicting information, it’s hard to know what’s true and what isn’t.

But it’s so important to understand the facts. Here are some of the most common claims  about prostate cancer supplements and information about the accuracy of these claims.

Claim: Selenium and Vitamin E Can Prevent Prostate Cancer

At one time, there were pre-clinical studies suggesting that high doses of selenium and vitamin E could prevent prostate cancer. The Selenium and Vitamin E Cancer Prevention Trial (SELECT) tested this claim. Thousands of men were randomized during this study, with some taking selenium, vitamin E, a combination of the two or no supplement at all.

Conclusion: The trial showed no benefit to taking these supplements. It also suggested that selenium and vitamin E may have increased prostate cancer risk or the risk of developing diabetes. For this reason, neither product is recommended. However, a review of over the counter prostate care supplements shows that about 40 percent of them still contain selenium or vitamin E.

Claim: Saw Palmetto Can Prevent Prostate Cancer

Saw palmetto has been used for years to treat benign prostatic hypertrophy (BPH), or an enlarged prostate. Several papers have suggested that this product may be as effective as some prescription products, although others dispute this.

Conclusion: There’s little data about the benefit of saw palmetto for prostate cancer prevention, but some ongoing trials are examining this. Small trials have suggested that men who have elevated PSA (prostate-specific antigen) levels from prostate cancer may benefit from saw palmetto temporarily. Saw palmetto generally has few side effects when taken appropriately, but there have been issues with contamination of the product in the past.

Claim: Vitamin D Can Lower Your Prostate Cancer Risk

Vitamin D has been examined in different malignancies. These trials are very hard to do, as people in different sections of the world have different amounts of sun exposure and different dietary intake of vitamin D. There still isn’t definitive evidence that vitamin D supplements prevents prostate cancer, but prostate cancer mortality may be lower in men who already take vitamin D supplements. The exact dose necessary is still unknown, but blood work can be done to determine one’s vitamin D level.

Conclusion: It’s unclear whether routine supplements can prevent prostate cancer.

Claim: Prescription Therapy Has Benefits for Prostate Cancer Prevention

Finasteride and dutasteride are both currently used for men with BPH, a benign increase in the size of the prostate. The drugs help to shrink the prostate and are known as 5 alpha reductase inhibitors. Both agents were reviewed during clinical trials and were shown to reduce prostate cancer development by about 20-25 percent. Unfortunately, there also may have been a link between a higher risk of prostate cancer development in men who were eventually diagnosed with the disease. It’s not certain that these drugs led to that higher risk or whether it was purely coincidence. The FDA declined to approve either agent for prevention purposes because of this potential risk.

Conclusion: While there are agents that help prevent prostate cancer, there are risks associated with them, and they are not currently recommended for prevention.

Claim: Red Meat Can Increase Your Risk for Prostate Cancer

There certainly is evidence that diets high in red meat can be associated with higher risks of prostate cancer.

Conclusion: The amount needed to increase this risk is still unclear.

Claim: Fruits, Vegetables and Tea Reduce Your Risk for Prostate Cancer

Some studies have shown that people who consume diets high in fruits and vegetables are less likely to develop prostate cancer. Studies also have shown that regions that consume high amounts of tea may have less prostate cancer than other sections of the world, but it remains unclear whether tea consumption is the sole reason behind this.

Conclusion: The level of fruit and vegetable consumption necessary to reduce prostate cancer risk remains unclear. As far as tea goes, it’s not clear whether this is the main factor for lower prostate cancer rates in regions with high tea consumption. Overall, it is difficult to know how much of a person’s diet needs to be modified to either raise or lower the risk of cancers in general. However, a good rule of thumb is “everything in moderation”.

Claim: Exercise Can Reduce Your Risk for Prostate Cancer

Data has consistently shown that people who exercise have lower cancer risks than those who don’t. Cardiovascular exercise balanced with mild to moderate weight lifting may be best for lowering your cancer risk, but just how much of it is still unclear. Additionally, British studies have shown that men in their 50s with more frequent ejaculation may have lower rates of prostate cancer.

Conclusion: Physical exercise is important for many reasons and should be encouraged, but whether it will prevent malignancies remains unclear.

There is no single way to prevent prostate cancer, but it is extremely important to talk to your doctors and discuss things such as PSA screening and direct rectal exams. The best way to treat prostate cancer, and most malignancies, is to be proactive, take care of your health and identify any problems as soon as possible.

Have more questions about prostate cancer? Learn more about it here.