Green Tea

Diabetes, Weight loss, Age related illnesses | January 22, 2018 | Author: Naturopath

age related, diabetes, weight loss

Green Tea

Green tea is a popular beverage in Asian culture—renown for its health benefits. Its use dates back 5,000 years, where it was drunk to maintain alertness and formed part of various traditional ceremonies. It is now well known that green tea improves cardiovascular health, reduces the risk of cancer and helps with weight loss. 

Green and black tea—what’s the difference?

Green tea comes from the same plant as black tea. The leaves from the Camellia sinensis plant are harvested at a younger age and consumed fresh to produce green tea.

Green and black tea—what’s the difference?Black tea is harvested later when the leaves are darker and oxidised. Green tea and the partially fermented oolong tea are popular in Asia. Whereas, black tea is the preferred beverage in many English-speaking countries. 
Because Green tea is less processed it retains more of its nutrients and antioxidants than black tea.

Green tea is also called Chinese tea, camellia tea, Matsu-cha, green Sencha tea, Japanese tea and Yame tea.

Antioxidants in green tea

The most abundant antioxidants in green tea is predominantly polyphenols which include:

  • Catechins
  • Epicatechins
  • Epicatechin gallate (ECG)
  • Epigallocatechin gallate (EGCG)
  • Proanthocyanidins

Green tea contains about 3% caffeine but is less likely to give you that strong caffeine hit and jitters compared to other caffeinated beverages. This may be due to its theanine content which assists in concentration and relaxation.

What about matcha green tea…

What about matcha green tea…Matcha is finely ground powder of specially grown and processed green tea leaves.

It is considered an antioxidant powerhouse—with much higher amounts of polyphenols such as epigallocatechin gallate.

Matcha tea can be drunk in the same way as traditional tea or added to foods to boost its nutritional value.

What the research shows

Green tea is one of the most widely studied food and there are thousands of studies to back up its health claims. These range from weight loss, reducing cholesterol, preventing cancer and providing cardiovascular protection.

Brain health

What’s good for your heart is good for you brain too! Blood vessels deliver oxygen and nutrients to our brain and if blood flow is affected, especially if there is plaque in the arteries, this can result in impaired function. Green tea has been shown to help block the formation of plaques that are linked to Alzheimer's disease and improves cerebral blood flow.

In one Swiss study, MRIs revealed that people who drank green tea had greater activity in the working-memory area of their brains. These findings provide evidence for the beneficial effect of green tea on cognitive functioning and might help to assess the efficacy of green tea for the treatment of cognitive impairments in disorders such as dementia.
Click Here For Article

Heart health

Heart healthEpidemiological studies suggest that regular green tea consumption is associated with a reduced risk of cardiovascular disease. Researchers believe this is due to it potent antioxidant effects and ability to reduce LDL, total cholesterol and blood pressure. Studies have indicated that green tea provides protection against stroke, atherosclerosis (plaque in arteries) and reduces your risk of death from cardiovascular disease.
Click Here For Article

What about weight loss?

Tea catechins, especially EGCG, appear to have antiobesity effects. Studies have found that green tea increases thermogenesis—a metabolic process which allows your body to burn more calories. They have also found that green tea consumption reduces food intake, decreases leptin levels and reduces body weight.

Diabetes

Animal and human studies have identified that green tea polyphenols reduce serum glucose levels and improve kidney function in diabetes. Due to their ability to protect nerve cells they may also be helpful in preventing diabetic neuropathy. A meta-analysis involving 22 randomised controlled trials involving 1584 participants found a significant decrease in fasting blood glucose over a 12 weeks period.

Cancer prevention

Studies of green tea in individual cancers show some positive effects.

Cancer preventionSupportive evidence is most consistent for breast, ovarian, endometrial and prostate cancers.
Click Here For Article

There is also evidence to suggest some benefit in colorectal and pancreatic cancers and leukaemia— however more studies need to be done in these areas.

Women who drank three or more cups daily had a reduction in the risk of breast cancer and its re-occurrence.

Researchers believe this may be due to the aromatase-inhibiting action of green tea, beneficial for women who are premenopausal.
Click Here For Article

Osteoporosis

New research from Hong Kong found that green tea may benefit bone health and has the potential to prevent and treat osteoporosis. They found that one catechin in particular, epigallocatechin, stimulated the action of a key enzyme that promotes bone growth by up to 79%. The effect of boosting epigallocatechin also increased the level of bone mineralization in the cells, which strengthens bones.
Click Here For Article

How to brew the perfect cup

  • To avoid damaging the antioxidants in green tea it is recommended to use water before it boils, about 160-170 degrees
  • Add a slice of lemon to improve the flavour and add a burst of vitamin C to improve the absorption of antioxidants
  • Avoid adding dairy as this blocks the absorption of the catechins
  • Buy an excellent quality product, as they usually contain greater levels of polyphenols

Are there any safety concerns?

Usual dietary consumption appears safe but if you are pregnant or highly sensitive to caffeine you might want to restrict your intake. Teeth staining is also possible due to the tannins, but to avoid this simply rinse your mouth with water afterwards. Another concern with green tea is that it inhibits the absorption of iron and should be taken away from iron supplements or foods containing iron.

www.superpharmacy.com.au  Australia’s best online discount chemist

References

Braun L, Cohen M. Herbs and natural supplements: An evidence based guide vol. 2. Churchill Livingstone, Australia

https://www.webmd.com/food-recipes/features/health-benefits-of-green-tea#1

Islam MA. Cardiovascular effects of green tea catechins: progress and promise. Recent Pat Cardiovasc Drug Discov. 2012 Aug;7(2):88-99

https://www.ncbi.nlm.nih.gov/pubmed/22670802

Chacko SM, et al. Beneficial effects of green tea: a literature review. Chin Med. 2010 Apr 6;5:13

https://www.ncbi.nlm.nih.gov/pubmed/20370896

Schmidt A, et al. Green tea extract enhances parieto-frontal connectivity during working memory processing. Psychopharmacology (Berl). 2014; 231(19):3879–3888

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4159594/

Ko CH, et al. Effects of tea catechins, epigallocatechin, gallocatechin, and gallocatechin gallate, on bone metabolism. J. Agric. Food Chem. 2009, 57 (16):7293–7297

http://pubs.acs.org/doi/abs/10.1021/jf901545u

backBack to Blog Home