What is Green Tea?
Native to Asia, green tea is an aromatic beverage that is one of the most consumed in the world. It is commonly prepared by pouring hot water over unfermented leaves of the Camellia sinensis plant. Though green tea is derived from the same plant as black tea, it is much healthier. Unlike black tea, the way green tea is processed prevents too much oxidation which preserves its taste and nutrients. Its high nutritional profile is also known for its many health benefits.
Studies have shown that green tea’s active components, polyphenols and catechins, are powerful antioxidants. According to several studies, the most compelling of these components is epigallocatechin gallate (EGCG) which has restorative properties for a variety of autoimmune and immunosuppressive diseases. Further, its therapeutic benefits cover a range of cancers including gynecological cancers that involve the breast, cervix, and uterus.
How Does Green Tea Benefit Patients with Gynecological Cancers?
For the most common cancers among women, green tea has proven its powerful benefits as it contains more than 2,000 bioactive components supporting health. EGCG receives the most attention as it is most abundant and potent. This natural antioxidant helps reduce free radical formation in the body, thereby preventing cell damage. When it comes to gyneocological cancers, EGCG is therapeutically powerful. In fact, green tea has proven to be 100 times more powerful than Vitamin C and 25 times more powerful than Vitamin E.
Green Tea Benefits for Breast Cancer
Out of all cancers, breast cancer is the second leading cause of death in women. As of the latest reporting year (2015), nearly a quarter million new cases were disclosed in the United States. For every 100,000 women, there are 125 new diagnoses and 20 deaths. Statistics show that one in 8 women will be diagnosed with breast cancer in her lifetime, but numerous studies also present the powerful benefits of drinking green tea to prevent breast cancer, as well as stop it in its tracks.
- EGCG stops breast tumors from growing.
- EGCG suppresses the breast cancer gene if it is present.
- EGCG treats contributing factors of breast cancer.
- EGCG provides mechanistic actions in growth factor signaling, angiogenesis, and fat metabolism in breast cancer patients.
- EGCG is helpful in reducing estrogen metabolites that cause breast cancer.
In addition to EGCG, caffeine in green tea has shown to diminish the recurrence of growing breast tumors. Green tea has also be reported to be a strong chemo-preventative and chemotherapeutic by the Pharmacology journal. When consuming prescription drugs such as Tamoxifen, breast cancer treatment is much more effective when green tea is added.
Green Tea Benefits for Cervical Cancer
Cervical cancer is usually a very slow growing cancer, but certain circumstances can spread it quickly. Nearly 13,000 new cases and more than 4,000 deaths are reported annually in the United States. One of the biggest risk factors for cervical cancer is human papillomavirus (HPV) infection. The good news is that green tea’s antioxidants are extremely helpful in inhibiting both infection and cancer.
Two compounds, EGCG and polyphenol E, have been reported to inhibit the proliferation of HPV-immortalized and HPV-positive cancer cells. Adeno and squamous carcinoma seem to react to these compounds more than other carcinomas of the cervix. Out of the two compounds, EGCG was most effective on growth inhibition and apoptosis of cervical cancer. The phytonutrients and catechins of green tea have also proven to significantly stop the cervical cancer from progressing. Specifically, EGCG and another antioxidant called theaflavin inhibit tumor growth and induce apoptosis (tumor cell death).
Green Tea Benefits for Endometrial or Uterine Cancer
Endometrial cancer, sometimes referred to as uterine cancer, is a type of cancer that begins in the lining of a female womb or uterus. The latest data reports nearly 56,000 new cases and more than 10,000 deaths per year in the United States. The cause of this type of cancer is not known. However, the beneficial properties of green tea have shown to be beneficial.
In January 2018, Cancer Letters reported that the [EGCG in green tea serves as a novel angiogenesis inhibitor in endometrial cancer](https://www.cancerletters.info/article/S0304-3835(17%2930623-7/fulltext). Another study published in Gynecologic Oncology suggested that [EGCG reduces the amount of vascular endothelial growth factor (VEGF) secreted into the supernatants endometrial cancer cells](https://www.gynecologiconcology-online.net/article/S0090-8258(09%2900100-0/fulltext).
How Much Green Tea is Beneficial for Gynecological Cancers?
If you have cancer, drinking green tea may be very beneficial for lowering your risk for the disease. Studies have shown that women who drank the most green tea had the least spread of breast cancer – especially those who are premenopausal.
Women who drank at least five cups per day before being diagnosed with cancer had the least risk for recurrence after treatment. Women who drank three cups or more of green tea per day are 37 percent less likely to develop cancer compared to those who don’t drink it. Based on research, the following is a good recommendation for how many cups of green tea you should drink daily:
- For Prevention = 3 to 5 cups
- For Therapeutic Purposes = 5+ cups
Does Green Tea Have Caffeine?
Generally, green tea has a lower caffeine content than black tea and brewed coffee. However, a specific level is difficult to define as that depends on the type of green tea, how it was processed, as well as how it was prepared.
According to a test conducted by the Journal of Food Science on dozens of commercial brands, each 8 ounce cup of green tea varied from 11 to 47 milligrams (mg.) of caffeine, though other sources recorded upwards of 60 mg. for one brewed cup. In comparison, each cup of black tea averaged 14 to 61 mg. while brewed coffee averaged 95 to 200 mg. per cup.
If you are sensitive to caffeine and can’t tolerate even the low amounts in green tea, you may opt for a brand that provides a decaffeinated version. Or, you may opt for a decaffeinated green tea supplement.
What if I Don’t Like the Taste of Green Tea?
Quality matters when choosing tea bags or loose leaf green tea. High quality teas will be cultivated without the use of toxic chemicals. Once harvested from the Camellia sinensis plant, the leaves will be quickly heated by pan firing or steaming and then dried to prevent as much oxidation as possible. This process will keep the green leaves from turning brown and altering their taste.
It may take a bit of investigating to find the right brand of green tea for your personal taste buds, but green tea may have a funky taste if it’s not prepared properly as well. Be sure to use pure water such as reverse osmosis or spring water. City water can have a ton of chemicals such as chlorine that will alter the taste of your tea. Bitterness can also be caused by infusing your tea for too long. Three to five minutes is plenty of time for extraction.
The recommended serving of green tea is 3.5 grams to 10 ounces of waters. You may also decrease the amount of tea by 0.5 grams until you get the flavor you enjoy most. If you still find that you don’t like the taste of green tea after experimenting, you may choose a green tea supplement that contains a high amount of EGCG.
Is Green Tea Safe?
Most adults consume 200 to 300 mg. of caffeine per day which equates to about one to three cups of brewed coffee. Any more than this can cause negative side effects. Too much caffeine can leave you jittery, nervous, and restless. It may also cause a condition called caffeine intoxication which results in nausea, anxiety, heart palpitations, dizziness, and insomnia. Based on 740 caffeine studies, researchers determined safe limits of caffeine as follows.
- Adults – 400 mg.
- Pregnant Women – 300 mg.
- Children & Teens – 2.5 mg.
Since the average cup of green tea contains approximately 25 mg., the upper recommended limit of five cups is well beneath this threshold for adult consumers. However, caffeine is a stimulant and some people are sensitive to it.
Where Can I Buy Green Tea?
Green tea can be purchased at your local supermarket or supplement shop. Be sure to select a high quality brand. You may also choose a supplement for convenience or it you just don’t like the taste of the tea. Be sure it contains a good amount of EGCG. Following are a few of my favorites.