Black Tea consumption, according to this study done on mice at Harvard University lowered DHT levels by 72% and raised testosterone by 35%. Finasteride, (Propecia/Proscar) reduces DHT levels in both male humans and rats by 70%.
Nutrition and Cancer
Soy Phytochemicals and Tea Bioactive Components Synergistically Inhibit Androgen-Sensitive Human Prostate Tumors in Mice
Nutrition/Metabolism Laboratory, Department of Surgery, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA
Although high doses of single bioactive agents may have potent anticancer effects, the chemopreventive properties of the Asian diet may result from interactions among several components that potentiate the activities of any single constituent. In Asia, where intake of soy products and tea consumption are very high, aggressive prostate cancer is significantly less prevalent in Asian men. The objective of the present study was to identify possible synergistic effects between soy and tea components on prostate tumor progression in a mouse model of orthotopic androgen-sensitive human prostate cancer. Soy phytochemical concentrate (SPC), black tea and green tea were compared with respect to tumorigenicity rate, primary tumor growth, tumor proliferation index and microvessel density, serum androgen level and metastases to lymph nodes. SPC, black tea and green tea significantly reduced tumorigenicity. SPC and black tea also significantly reduced final tumor weights. Green tea did not reduce final tumor weight, although it tended to elevate (P = 0.14) the serum dihydrotestosterone (DHT) concentration. The combination of SPC and black tea synergistically inhibited prostate tumorigenicity, final tumor weight and metastases to lymph nodes in vivo. The combination of SPC and green tea synergistically inhibited final tumor weight and metastasis and significantly reduced serum concentrations of both testosterone and DHT in vivo. Inhibition of tumor progression was associated with reduced tumor cell proliferation and tumor angiogenesis. This study suggests that further research is warranted to study the role of soy and tea combination as effective nutritional regimens in prostate cancer prevention.
Although the DHT lowering effect of Black Tea `was not mentioned in the abstract, we obtained and reviewed the entire study including this revealing snippet:
Combined effects of soy phytochemicals and tea on serum testosterone and DHT concentrations.
Mice treated with black tea (via standard,steeped beverage)tended to have a greater serum testosterone concentration (34.4%, P = 0.50) and had a 72% lower DHT concentration than controls (P < 0.05), suggesting that black tea may contain components that inhibit the activity of 5 -reductase, an enzyme that converts testosterone to the more bioactive DHT.
This study also showed that the consumption of Green Tea as a beverage combined with Soy Isoflavone Concentrate significantly reduced DHT levels, and to some degree testosterone. Curiously it was found that the singular consumption of Green Tea raised both testosterone and DHT levels.
The implications of potential benefits to humans with Androgenetic Alopecia are significant.
It would appear reasonable based upon these findings that exclusive consumption of Black Tea or Black Tea Extract (Theaflavins) would likely reduce serum DHT to the same level as Propecia, and that the concurrent consumption of Soy Isoflavones or Soy Isoflavones with Green Tea would produce an additive effect.
Human studies done thus far on Soy and its effects on reproductive hormones in men in males indicate no apparent negative effect. It has also been established that Green Tea to some degree, suppresses androgen receptor signaling and inhibits both 5 alpha reductase isozymes. Green Tea and Grape Seed Extracts have been successfully combined with Taurine by L’Oreal to stop hair loss and promote hair growth. Based on this study however, some may feel that Green Tea should only be consumed with Soy. Given Green Tea’s multitude of anti-androgenic actions and the increase in SHBG (low levels of SHBG are associated with male pattern hair loss) that Green tea consumption causes, it is our position that Green Tea, even if singularly consumed, will likely benefit those with hair loss.
It is well established that the incidence of male and female pattern balding in the rural Orient is a small fraction of what it is here in the United States, and that the incidence of Androgenetic Alopecia among Asians who live in the U.S. is much higher than those living in the Orient. Soy based foods, a dietary staple, and the regular beverage consumption of Green and Black Teas factor significantly, and are perhaps causative, in this phenomenon.
The sexual side effects, including oft occurring Gynocomastia,(male breast enlargement), and the more ominous potential neurological side effects associated with finasteride (Propecia/Proscar), uncovered in the last few years, seem to make it less of a viable option. This compelling in vivo study provides direct evidence that blood levels of DHT can be reduced to a level equivalent to that of Propecia, in a natural, healthy, more cost effective way.
Exclusive consumption of strongly brewed Black Tea, as done by rats in this study to obtain a decrease in DHT and increase in Testosterone would not be practical for humans. Black Tea Extracts (Theaflavins) are available and contain Black Tea constituents at concentrations well above what would be obtainable via oral consumption.
Theaflavin Standardized Extract
An increasing number of scientists recognize the critical need to protect the arterial wall against low-density lipoprotein (LDL) oxidation and inflammatory insults. Research has shown that unique extracts present in black tea called theaflavins can have multiple applications for arterial health.
Theaflavin Standardized Extract contains a number of beneficial flavonoids found naturally in tea leaves that help support levels of cholesterol that are already within the normal range.
Theaflavins have been shown in human studies to protect against LDL oxidation and favorably affect endothelial function, thus helping to maintain healthy circulation.
Scientists have also found that black tea flavonoids possess strong antioxidant properties, which can help mitigate oxidative damage to cells and tissues from free radicals. In addition, theaflavins have been found to be helpful in down-regulating key inflammatory mediators, (several of which factor significantly into hormone related hair loss) in the body, thus helping to preserve cellular integrity.