Polyphenols Halt Prostate Cancer Growth
Posted By Dr. Mercola | June 29 2010
Scientists believe they now know exactly why polyphenols, such as those found in red wine and green tea, inhibit cancer growth. The antioxidants produce a combined effect to disrupt an important cell signaling pathway necessary for prostate cancer growth.
The SphK1/S1P signaling pathway plays a role both in prostate cancer and in other cancers such as colon cancer, breast cancer, and gastric cancers.
"Scientists conducted in vitro experiments which showed that the inhibition of the sphingosine kinase-1/sphingosine 1-phosphate (SphK1/S1P) pathway was essential for green tea and wine polyphenols to kill prostate cancer cells ... Human prostate cancer cells were implanted in the mice and results showed a dramatic decrease in tumor size in the mice drinking the EGCG or polyphenon E mixtures."
Dr. Mercola's Comments:
Polyphenols are potent antioxidant compounds in plant foods and their ability to fight numerous health conditions has been the subject of much exciting research in recent years.
At the center of the limelight are the polyphenols in green tea and red wine, both of which have shown powerful anti-cancer effects. In the latest research, it appears the antioxidants disrupt a cell signaling pathway that is necessary for prostate cancer to grow.
How Green Tea Polyphenols May Fight Cancer
Polyphenols in tea, which include EGCG (epigallocatechin gallate) and many others, are protective against many types of cancer. For instance, women under 50 who drank three or more cups of tea a day had a 37 percent reduced risk of developing breast cancer, and women who regularly drink five or more cups of green tea daily appear about 20 percent less likely to develop stomach cancer.
Other studies have also highlighted tea's potential to fight skin cancer, ovarian cancer, colon cancer, and prostate cancer, and compelling evidence suggests that the polyphenols in green tea may be even more effective at fighting the progression of cancer than the antioxidants found in red wine and grapes.
There are several primary ways that green tea, and also green tea extract, may help prevent cancer:
- Green tea extract works by affecting actin remodeling, an event that allows cancer cells to move and invade nearby healthy tissue.
- When a human moves, the muscles and skeletal structure function together to assist that movement. In order for cancer to grow and spread, the malignant cells must be able to move; this movement depends on actin remodeling.
- Green tea extract makes the cancer cells more mature and joins them together more closely (a process referred to as cell adhesion).
- Both the maturity of the cells, as well as the occurrence of adhesion, inhibits their mobility, thus hindering spreading.
The polyphenols in green tea may constitute up to 30 percent of the dry leaf weight, so, when you drink a cup of green tea, you're drinking a fairly potent solution of healthy tea polyphenols. Green tea is the least processed kind of tea, so it also contains the highest amounts of EGCG of all tea varieties.
Keep in mind, however, that many green teas have been oxidized, and this process may take away many of its valuable properties. The easiest sign to look for when evaluating a green tea's quality is its color: if your green tea is brown rather than green, it's likely been oxidized.
My personal favorite is matcha green tea because it contains the entire ground tea leaf, and can contain over 100 times the EGCG provided from regular brewed green tea.
If you're not familiar with tea you may have never heard of matcha tea. Rather than being steeped and strained like typical tea, matcha tea is made of tea leaves ground into a powder, and you mix the powder right into water.
The matcha tea is a vibrant bright green, and is far less processed and of much higher quality than most other green teas, so you also avoid the risk of ingesting high levels of fluoride, lead, and aluminum, which can be found in inferior teas of all kinds, including green teas.
Does Red Wine Fight Prostate Cancer Too?
Red wine contains resveratrol, a polyphenol found in a number of plants, including grape skins, raspberries, mulberries and peanuts. Among its many health-boosting properties is a known ability to fight cancer.
Resveratrol deeply penetrates the center of your cell's nucleus, giving your DNA time to repair free radical damage. It also supports cell functions in your heart and brain so that you can help prevent the rampant spread of cancer cells at any stage.
Further, resveratrol's anti-inflammatory properties help prevent certain enzymes from forming that trigger tumor development. It also helps cut down cell reproduction, which helps reduce the number of cell divisions that could contribute to the progression of cancer cell growth, and may also reduce testosterone levels, which promote prostate cancer growth.
Resveratrol is found in abundance in red wine, and it's highly soluble in alcohol, meaning your body may absorb more of it from red wine than from other sources. This may be why drinking a glass of red wine a day has been said to reduce men's prostate cancer risk by 50 percent.
I do not, however, suggest drinking large amounts of red wine, as the alcohol is a poison to your system.
Instead, you can get some resveratrol from your diet by eating grapes (muscadine grapes have the highest concentration of resveratrol in nature because of their extra thick skins and numerous seeds where it is concentrated), cocoa, dark chocolate and peanuts, but it will likely be difficult to get a therapeutic dose, especially since these are all foods I recommend you eat only in moderation.
The other option is to take a resveratrol supplement (which is one of the few supplements I personally take every day), and in this case be sure to look for one made from a whole food complex that includes muscadine grape skin and seeds.
Your Diet is a Potent Way to Lower Your Prostate Cancer Risk
Remember, it's not only polyphenols in green tea and grapes that can help you lower your prostate cancer risk.
Aside from skin cancer, prostate cancer is the most common cancer in American men. It's also the second leading cause of cancer death, behind lung cancer.
About one in six men will be diagnosed with prostate cancer during their lifetime, so it's important to take steps to reduce your risk now.
Fortunately, your diet can either help or hinder cancer development or progression. Eating higher amounts of vegetables and fruit, and avoiding high energy intake, processed meat, and excessive dairy products and calcium may be helpful for preventing prostate cancer, and in treating patients already diagnosed with it.
One 2009 study also identified the following foods as being particularly beneficial against prostate cancer:
- Green tea
- Vitamin E
- Alkalinize your system with loads of raw foods
Two More Important "Vitamins" for Prostate Cancer
No discussion of prostate cancer, or any cancer, avoidance would be complete without mentioning vitamin D. There are, in fact, more than 800 scientific studies confirming the link between vitamin D deficiency and multiple types of cancers, including prostate cancer.
According to a study published last year, men with higher levels of vitamin D in their blood were seven times LESS likely to die from prostate cancer than those with lower amounts. Vitamin D has a protective effect against cancer in several ways, including:
- Increasing the self-destruction of mutated cells (which, if allowed to replicate, could lead to cancer)
- Reducing the spread and reproduction of cancer cells
- Causing cells to become differentiated (cancer cells often lack differentiation)
- Reducing the growth of new blood vessels from pre-existing ones, which is a step in the transition of dormant tumors turning cancerous
Overall, getting a safe amount of sun exposure on a regular basis, or taking an oral vitamin D3 supplement could reduce your risk of all cancers by at least half! So please take a few minutes to learn how to safely optimize your vitamin D levels today.
Next, vitamin K2 has also been found to offer significant protection against prostate cancer. One 2008 study by the European Prospective Investigation into Cancer and Nutrition (EPIC) found that increased intake of vitamin K2 may reduce your risk of prostate cancer by 35 percent.
Interestingly, the potential benefits of vitamin K2 were most pronounced for advanced prostate cancer.
It is such an important vitamin that, although I don't typically recommend adding extra supplements to your diet, vitamin K is one of the few supplements you should seriously consider because many people don't get nearly enough of it on a daily basis through the foods they eat (natto and fermented cheeses are rich sources of vitamin K2).
Although the exact dosing is yet to be determined, one vitamin K expert, Dr. Cees Vermeer, recommends between 45 mcg and 185 mcg daily for adults. You must use caution on the higher doses if you take anticoagulants, but if you are generally healthy and not on these types of medications, I suggest 100 mcg daily.
Please note that if you've experienced stroke, cardiac arrest, or are prone to blood clotting, do not take vitamin K without consulting your physician first.
Another important note is that vitamin K is a fat-soluble vitamin, which means that dietary fat is necessary for its absorption
Take Action to Prevent Prostate Cancer Now
Most cases of prostate cancer do not occur until after men turn 50, but in recent years there has been a steady rise in the percentage of men in their 30s and 40s with both prostate problems and prostate cancer, primarily as a result of poor diet and increasing environmental pollution. So it's a good idea to start taking steps to lower your risk now.
Along with including polyphenols, vitamin D, and vitamin K2 in your healthful lifestyle, here is a list of 14 additional guidelines and strategies to help you avoid and treat prostate (and breast) cancer.
- Cooking and vitamin D retention
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- Study suggests whole diet approach to lower CV risk has more evidence than low-fat diets (PR)