Green tea originated in China more than 4000 years ago. Since then, interest in the tea’s benefits has made it popular around the world. Now, green tea is used as a beverage, a medicine, and an ingredient in health foods, cosmetic products, and dietary supplements.
Green tea comes from the leaves of Camellia sinensis; as do black, white, and oolong teas. However, green tea is unique because it undergoes minimal oxidation during processing. As a result, this tea contains higher concentrations of polyphenols.
Polyphenols are antioxidants. They scavenge for free radicals and then neutralize the harmful toxins. Green tea is particularly high in epigallocatechin gallate (EGCG) — a specific polyphenol type. In addition to improving overall health, EGCG is linked to weight loss.
Free radicals and toxins damage cells and DNA. This damage speeds the aging process, and increases cancer risk. By neutralizing free radicals and toxins, green tea’s polyphenols protect and repair cells, and may help prevent cancer.
The antioxidants in green tea are vasodilators — they make blood vessels more flexible and prevent arteries from clogging. Researchers say drinking green tea may reduce the risk for heart disease and stroke by 10-20%. A study that followed more than 37,000 people for 13 years showed those who drank green tea were less likely to die from heart disease.
A report of 20 clinical studies concluded, “The consumption of green tea catechins is associated with statistically significant reductions in total [cholesterol] and LDL cholesterol levels.” Lowering cholesterol not only benefits the heart, it also decreases diabetes risk.
In addition, green tea burns calories and promotes fat loss. After consuming green tea extract for 90 days, obese study participants reduced body fat lost more than 30 lbs. Researchers also say green tea lowers blood sugar, which reduces fat storage and sugar cravings.
Because green tea contains caffeine, it boosts energy and improves mental alertness by stimulating the central nervous system. Caffeine also suppresses cravings and enhances green tea’s ability to burn fat.13]
Green tea is likely safe for most adults, according to the National Health Institutes. However, drinking too much may be unsafe due to the caffeine. A safe caffeine dosage is 400 mg or less per day. An 8 oz. cup of green tea has between 24 and 40 mg caffeine. Using over 6 grams cinnamon may irritate the mouth and lips, resulting in sores.
Caffeine may cause side effects such as:
- Irregular Heartbeat
Women who are pregnant or nursing should not drink more than 2 cups of green tea a day. Consuming more may increase the risk for miscarriage.
If you have any of the following conditions, drinking green tea may make it worse:
When applied to the skin, cinnamon may cause skin irritation and allergic reactions.
- Heart Conditions
- Irritable Bowel Syndrome
- High Blood Pressure
Green tea may interact with several popular medications (e.g. birth control pills). Talk to your doctor or pharmacist before consuming green tea.
The following dosages were used during studies involving green tea as a beverage:
- For Increasing Alertness: 3 cups of tea daily
- For Lowering Cholesterol: 10 or more cups of tea daily
- For General Benefits: 3 cups of tea daily
- For Cardiovascular Health: 3-6 cups of tea daily]
Every 8 oz. green tea contains 25-106 mg EGCG.
Due to the risk associated with consuming too much caffeine, do not drink 10 or more cups of green tea without consulting a medical professional.]
For weight loss from supplements, this green tea extract dose was used during a clinical study:
- 300 mg daily]
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