Green Tea Cancer Benefit
Unproven And Yet Valuable?

In 2005 and 2006, FDA rejected green tea cancer fighting claims. They concluded that its anti-cancer properties are unproven. What should we make out of this?

According to Barbara Schneeman of FDA, green tea does not reduce the risk of cardiovascular (heart) disease.

Here is what she wrote in 2006:

FDA concludes there is no credible evidence to support qualified health claims for green tea or green tea extract and a reduction of a number of risk factors associated with CVD (cardiovascular disease).

This is not the first time the FDA has spoken out. The year before, it said "green tea does not reduce the risk of breast, prostate or any other type of cancer".

Why? Because there are insufficient green tea cancer studies to prove it.

In particular, more human trials are needed to clarify and further understand the scientific mechanisms involved.

Are You Concerned?

Is green tea just another health fad that has been drummed up by clever marketers?

What exactly does the science say?

Should you go ahead and start drinking green tea? Or is there a better alternative around?

Let me answer your first question first.

How Does It Work?

green tea cancer

Green tea is extremely versatile. Studies involving cell culture and animals have found that it blocks cancer in a number of ways.

  • Powerful Antioxidants

One of the most powerful in nature, green tea antioxidants have been found to be over 100 times more effective in neutralizing free radicals than vitamin C, and 25 times more powerful than vitamin E.

The most important antioxidant is EGCG (epigallocatechin gallate). Studies have found that it reduces cellular damage that could lead to cancer.

  • Few Side Effects

Green tea based drugs may cure cancer without nasty side effects.

Unlike drugs such as Vioxx and Celebrex, studies suggest that EGCG destroys cancer cells without harming surrounding healthy cells.

  • Starve Cancer Cells

To reproduce quickly, cancer cells need many blood vessels to supply them with nutrients. Green tea blocks angiogenesis, or the development of new blood vessels, thus starving off these cancer cells from nutrients.

  • Kill Cancer Cells

Green tea turns off the growth genes and turns on the suicide genes in cancer cells. It works as a free radical just inside cancer cells, causing so much damage that the cancer cells commit suicide. A 2016 study published by a South Korean team concluded:

"EGCG induced [suicide] of cancer cells without adverse effects on normal cells. EGCG inhibited growth, invasion, and migration of HuCC-T1 cells. We suggest EGCG as a promising candidate for local treatment of [bile duct cancer cells]."

  • Block Cancer-Causing Enzyme

Overproduction of enzyme cyclooxygenase, COX-2 has been implicated as a factor in many diseases, including arthritis and cancer. Green tea inhibits the overproduction of COX-2.

Green tea also blocks enzyme dihydrofolate reductase (DHFR), which has been found to be a catalyst to cancer growth.

How Green Tea Blocks Cancer Growth

Still Unproven?

The mechanisms of green tea cancer fighting action are well understood. Like many other fruits and vegetables, it will help reduce your cancer risk.

What is less certain is this: If you are suffering from cancer, how can green tea help you?

With insufficient human trials, it will be dangerous for companies to market green tea products as cancer-preventive. After all, it is the job of the FDA to make sure solid research exists for any product claim.

If you are suffering from cancer, would consuming green tea extract tablets cure you?

I think not. Although they may do one day, such medicines do not yet exist.

If you are healthy but prone to suffering from cancer, should you start drinking green tea?

Absolutely yes. It is one of the best sources of antioxidants that exists on Mother Earth, considering its wide ranging health benefits, low costs and few side effects.

Green Tea Medical Benefits - Hear What The Doctors Say

Wide Ranging Benefits

In the last 10 years, green tea cancer preventive properties have been widely reported in many studies.

The evidence is so overwhelming that the United States National Cancer Institute is developing green tea compounds as cancer preventive agents in human trials.

From brain tumours to leukaemia, from lung cancer, stomach cancer, colon cancer, oesophageal cancer to bladder cancer, not to mention breast cancer, ovarian cancer and prostate cancer, green tea cancer studies have rewarded scientists with positive results.

Listed below are the highlights. If any area interests you, click on the link to read more.

New! Comments: Like This Story? Leave A Comment!


Anticancer activities of epigallocatechin-3-gallate against cholangiocarcinoma cells (2016). Kwak TW, Park SB, Kim HJ, Jeong YI, Kang DH. OncoTargets and Therapy 22 December 2016 Volume 2017:10 Pages 137—144.

Related Articles

Lung Cancer

Green tea protects from lung cancer by reducing cellular damage caused by cigarette smoke by 25%.

Skin Cancer

A study found that it protects against non-melanoma skin cancer by inhibiting harmful enzyme junk-2.

Brain Cancer

Two to five cups of green tea a day contains enough caffeine to block most aggressive brain tumor.


One cup of green tea a day reduces the risk of gallstones, gallbladder cancer and bile duct cancer by at least 27%.

Chronic Lymphocytic Leukaemia

Chronic lymphocytic leukaemia has no known cure, but a study offered a glimpse of what might be the future.

Prostate Cancer

A study shows that when used in conjunction with conventional treatment, green tea delivers more with fewer observed side effects.

Ovarian Cancer

One cup of tea a day reduces a woman's ovarian cancer risk by 24%. Each additional cup reduces the risk by another 18%.

Breast Cancer

A 2008 study using mice confirmed that drinking EGCG is beneficial for the prevention and treatment of cancer.

Oral Cancer

3 cups of green tea a day was found helpful to patients suffering from pre-cancerous lesion of oral cancer.

Pancreatic Cancer

Two studies, one population based, one laboratory based, suggest that green tea may prevent and treat pancreatic cancer.

Stomach Cancer

Regular green tea drinkers are half as likely to develop stomach and oesophageal cancer as compared to non drinkers.

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