Green Tea and Prostate CancerJuly 2017
By William Faloon
In the October 1992 issue of this publication, I wrote an article about the cancer prevention potential of green tea extract. I based my article on about 100 scientific papers.
If you search the National Library of Medicine database today, you’ll find over 1,000 studies relating to green tea and overall cancer prevention.
In June 2005, the FDA went to considerable effort to publish a position paper stating:
“…it is highly unlikely that green tea reduces the risk of prostate cancer.”1
This prompted me to write a rebuttal in the November 2005 issue of this magazine exposing flaws and omissions in the FDA’s report.2
The most egregious omission was a study presented at the 96th American Association for Cancer Research Meeting, where men with premalignant prostate disease were given 600 mg a day of a green tea extract supplement or placebo. The men taking green tea extract were 90% less likely to progress to prostate cancer compared to the placebo group after one year.3
While this study was relatively small, the FDA pretended as if this favorable data did not exist when disseminating their report questioning whether green tea had cancer protective effects.
The FDA later attacked a maker of green tea leaves that dared to state on their label: “green tea may prevent prostate and breast cancer.”
As reported in the July 2012 issue of this publication, a Federal Court ruled against FDA’s attempt to censor an anti-cancer claim on the box of these green tea leaves.4
Move forward to 2017 and the totality of evidence supporting a role for green tea in cancer prevention has greatly expanded.
If you enter “green tea and prostate cancer” into the PubMed.gov database, you can review around 400 published scientific studies on this specific topic.
The preponderance of these studies shows that green tea or its polyphenol extracts may lower prostate cancer incidence. A meta-analysis published in 2017 of some of these studies reveals prostate cancer risk reduction in response to higher green tea intake.5
This recent meta-analysis involved a comprehensive, systematic dose–response review to evaluate the association of green tea intake with prostate cancer risk.
This analysis of green tea catechins (polyphenols) and green tea consumption suggested a reduction in prostate cancer incidence.
Data from this March 2017 analysis found a dose-associated reduction of prostate cancer risk in men who drank green tea. The more green tea men drank, the lower their prostate cancer risk based on linear analysis.5
When this study evaluated green tea polyphenol (catechin) intake, there was an associated 62% reduction in prostate cancer risk based upon three randomized controlled human trials.5
Moffitt Cancer Center
Located in Tampa, Florida, Moffitt is one of 47 National Cancer Institute-designated Comprehensive Cancer Centers.6 It conducts clinical trials related to cancer prevention and control. Moffitt is ranked as one of the top conventional cancer hospitals in the Southeastern United States.
A team of Moffitt researchers conducted a randomized trial to assess the safety and effectiveness of the active components in green tea to prevent prostate cancer development in men who have premalignant lesions.
According to the Moffitt researchers:
“Laboratory studies have shown that substances in green tea called ‘catechins’ inhibit cancer cell growth, motility and invasion, and stimulate cancer cell death. Green tea catechins also prevent and reduce tumor growth in animal models. Epigallocatechin-3-gallate (EGCG) is the most abundant and potent catechin found in green tea responsible for these cancer prevention effects.”7
The goal of the Moffitt clinical trial was to evaluate if a one-year intervention with green tea catechins could suppress prostate cancer development in men who had high-grade intraepithelial neoplasia or atypical small acinar proliferation.
The Moffitt researchers used decaffeinated green tea capsules that contained a mixture of catechins that predominantly consisted of EGCG at a dose of 200 mg twice a day.
In this study, green tea extract capsules were compared to placebo pills in men with premalignant prostate lesions over a 1-year treatment period. Overall, the difference in the number of prostate cancer cases at the end of one year between the two treatment groups was not statistically significant.
However, in men who only had high-grade intraepithelial neoplasia at the beginning of the trial, there was a lower rate of progression to prostate cancer and development of atypical small acinar proliferation in the group taking green tea extract capsules.8
Atypical small acinar proliferation reflects a broad group of prostate lesions with insufficient changes in the cells to definitively diagnose prostate cancer.
In this study, men receiving the green tea extract had a decrease in PSA (prostate-specific antigen) levels, which is an indicator of reduced prostate cancer risk.
The title of the Moffitt Cancer Center press release was:
“Component in Green Tea May Help Reduce Prostate Cancer in Men at High Risk”7
While we at Life Extension® are gratified to see mainstream cancer researchers conduct this study, a higher dose of green tea extract may have produced better results, as was shown in an earlier 2006 study that used 600 mg a day.
A challenge in interpreting published studies about green tea is that different doses, different study durations, and other factors make it challenging to reach consistent outcomes. Most reports conclude with the researchers stating, “More human studies are needed.”
We at Life Extension don’t disagree about the value of more human studies. The undeniable fact is that more than 160,000 American men will be diagnosed with prostate cancer this year.9
If a high-potency green tea extract capsule could reduce these prostate cancer numbers anywhere near what some studies indicate, this would have an enormous beneficial impact on the health of aging men.
Don’t Forget About Diet
It is important to never rely on any single nutrient to reduce cancer risk. As has been extensively written in Life Extension Magazine®, one’s overall diet has an enormous impact on prostate and other cancer risk.10-12
The box on the next page is a summary we published in 2016 showing marked prostate cancer risk reductions in response to healthier eating patterns.
Reviewing these findings reveals the challenges in clinical studies that seek to assess if a single nutrient prevents cancer and other diseases. For instance, if too many men in a small study group are overeating cancer-causing foods, it could negate what effect the nutrient is really having.
In This Month’s Issue…
A fascinating article in this month’s issue describes new data showing those who consume green tea not only have lower cancer rates, but suffer fewer degenerative illnesses and live longer.
Another article reveals that nutrients like lutein used to protect against macular degeneration also improve night vision. We were the first to introduce lutein as a supplement back in 1985.
The article on page 76 further corroborates what we have long known, i.e., magnesium deficiency worsens insulin resistance, an underlying cause of type II diabetes.
Of particular interest to all of you is the article on page 24 that describes a new beverage that can function as an “alternative to coffee.”
Clinical studies reveal how this novel cocoa-spearmint drink mix boosts mental sharpness, focus, and attention, while improving microvascular circulation in the brain.
Every time you purchase a blood test, dietary supplement, or other product advertised in this magazine, you help us contribute more funds towards human age-reversal research endeavors.
By taking steps to preserve your health today, the more likely you will be able to benefit from remarkable advances emerging in the field of regenerative medicine.
For longer life,
William Faloon, Co-Founder
Life Extension Foundation Buyers Club
- Available at: https://www.fda.gov/food/ingredientspackaginglabeling/labelingnutrition/ucm072774.htm. Accessed April 17, 2017.
- Available at: http://www.lifeextension.com/Magazine/2005/11/awsi/Page-01. Accessed April 17, 2017.
- Bettuzzi S, Brausi M, Rizzi F, et al. Chemoprevention of human prostate cancer by oral administration of green tea catechins (GTCs) in high grade PIN subjects: a preliminary report from a 1 year proof of principle study. Cancer Research. 2005;65(9 Supplement):1041-.
- Available at: http://www.lifeextension.com/Magazine/2012/7/Another-Victory-Against-FDA-Censorship/Page-01. Accessed April 17, 2017.
- Guo Y, Zhi F, Chen P, et al. Green tea and the risk of prostate cancer: A systematic review and meta-analysis. Medicine (Baltimore). 2017;96(13):e6426.
- Available at: https://www.cancer.gov/research/nci-role/cancer-centers. Accessed April 21, 2017.
- Available at: https://moffitt.org/newsroom/press-release-archive/2015/component-in-green-tea-may-help-reduce-prostate-cancer-in-men-at-high-risk-moffitt-cancer-center-researchers-say. Accessed April 17, 2017.
- Kumar NB, Pow-Sang J, Egan KM, et al. Randomized, Placebo-Controlled Trial of Green Tea Catechins for Prostate Cancer Prevention. Cancer Prev Res (Phila). 2015;8(10):879-87.
- Available at: https://seer.cancer.gov/statfacts/html/prost.html. Accessed April 17, 2017.
- Available at: http://www.lifeextension.com/Magazine/2013/12/Impact-of-Diet-on-Prostate-Cancer-Risk-and-Mortality/Page-01. Accessed April 17, 2017.
- Available at: http://www.lifeextension.com/magazine/2007/2/cover_prostate/Page-01. Accessed April 17, 2017.
- Available at: http://www.lifeextension.com/Magazine/2013/12/Prostate-Cancer-Prevention-Controversy/Page-02. Accessed April 17, 2017.
- Ornish D, Weidner G, Fair WR, et al. Intensive lifestyle changes may affect the progression of prostate cancer. J Urol. 2005;174(3):1065-9; discussion 9-70.
- Yang M, Kenfield SA, Van Blarigan EL, et al. Dietary patterns after prostate cancer diagnosis in relation to disease-specific and total mortality. Cancer Prev Res (Phila). 2015;8(6):545-51.
- Yang M, Kenfield SA, Van Blarigan EL, et al. Dairy intake after prostate cancer diagnosis in relation to disease-specific and total mortality. Int J Cancer. 2015;137(10):2462-9.
- Antwi SO, Steck SE, Zhang H, et al. Plasma carotenoids and tocopherols in relation to prostate-specific antigen (PSA) levels among men with biochemical recurrence of prostate cancer. Cancer Epidemiol. 2015;39(5):752-62.
- Bashir MN, Malik MA. Case-control study of diet and prostate cancer in a rural population of Faisalabad, Pakistan. Asian Pac J Cancer Prev. 2015;16(6):2375-8.
- Askari F, Parizi MK, Jessri M, et al. Fruit and vegetable intake in relation to prostate cancer in Iranian men: a case-control study. Asian Pac J Cancer Prev. 2014;15(13):5223-7.
- Rosato V, Edefonti V, Bravi F, et al. Nutrient-based dietary patterns and prostate cancer risk: a case-control study from Italy. Cancer Causes Control. 2014;25(4):525-32.