Green tea, produced from leaves and buds of Camellia sinensis, is a well-known drink widely popular over the world. According to the study, drinking green tea has numerous benefits as well as some side effects. In this article, we are going to review the constituent, benefits, and effects of green tea on the human body at a glance.
Constituents of Green Tea:
Green tea is composed of (dry weight) [1]
- Protein 15%
- Amino acids 4%
- Fiber 26%
- Others carbohydrates 7%
- Lipids 7%
- Pigments 2%
- Minerals 5%
- Phenolic compounds 30%
- Oxidized phenolic compounds 0%
Benefits of Green Tea
The benefits of taking green tea at a glance. Read more about the Health Benefits of Fasting- Backed by Science
- Cancer: Though it is uncertain if green tea prevents cancer or not, the effect of its main constituent epigallocatechin-3-gallate [EGCG] on preventing cancer is quite positive.[2] EGCG can clean free radicals and protect cells from DNA damage.[3] Green tea prevents the proliferation of tumor cells and accelerates apoptosis.[4] Polyphenols of green tea can protect against damage that is caused by UV radiation.[5]
- Cardiovascular disease: Catechins of green tea can prevent oxidation, vascular inflammation, thrombogenesis, and atherogenesis.[6] The function of endothelial cells is improved by drinking green tea which inhibits atherosclerosis.[7] It is found that epigallocatechin-3-gallate (EGCG) of the green tea binds to the amyloid fibers of apo-1 which are responsible for atherosclerotic plaques. This binding converts the fibers into smaller soluble molecules.[8] By doing such act, green tea helps in preventing vessel block and cardiovascular diseases.
- Hyperlipidemia: A higher level of fat in the blood is referred to as hyperlipidemia. Higher levels of cholesterol and LDL (low-density lipoprotein) are reasons behind several types of arterial blocks. But the study finds that reduction of blood cholesterol and LDL are aided by the administration of green tea beverages. This leads our lipid profile to standard.[9]
- Glycemic control: The Glycemic index is a measurement of sugar in the blood. A high glycemic index means high blood sugar or glucose which is a reason behind diabetes. But green tea is effective in reducing glucose levels in the blood.[10] It has positive effects on insulin resistance.[11] That means the consumption of green tea can help to prevent type-2 diabetes.
- Anti-bacterial: As per research, green tea extracts have anti-bacterial activities.[12] It can help to eliminate antibiotic-resistant bacteria.[13] Presence of catechins and polyphenols in green tea are responsible for this activity. These two extracts of green tea damage the cell membrane of bacteria and destroy them.
- Teeth: The research found that green is good for periodontal health.[15] Green tea can shield against cavities. It also can protect against gum disease. Moreover, bad breath may be refreshed by drinking green tea. It may reduce oral bacteria and their activities. Bacteriocidal effects have been seen in green tea, only when you drink it without sugar.[14] This assists to promote the health of gums and teeth.
- Skin: Green tea has anti-inflammatory and anti-carcinogenic power which can work against several skin disorders, study suggests.[16] It also linked with skin cell rejuvenation.[17] Green helps to protect against harmful UV rays, increase microcirculation, and also modulate the skin properties of women.[18] So, you may drink green tea regularly if you suffer from such skin disorders.
- Others: Besides these, consumption of green helps bones to be stronger[19], to boost the immune function and suppress the autoimmune diseases[20], to protect neurons against Alzheimer’s disease and Parkinson’s disease[21], to act as anti-aging[22], to block rheumatoid arthritis[23], to prevent sleep apnea[27] and so on.
Read also> 10+ Effective Ways to Keep Your Heart Healthy
Side Effects of Green Tea
- Anemia: Excessive green tea drinking is linked with iron deficiency anemia, as per research.[25] The antioxidants present in green tea can hinder iron absorption and lead to anemia.[24] It may be prevented by adding lemon on tea as lemon contains vitamin C which helps in iron absorption.
- Stomach problem: Green tea contains caffeine and tannins which have negative effects on our body. They tend to increase the acidity level in the body and can lead to a disorder in the digestive system. It may cause vomiting.[26]
- Pregnancy: Pregnant women should avoid green tea. Caffeine, catechins, and tannic acids in green tea have been involved in pregnancy risks. Neural tube birth defects in babies may be caused by excessive drinking of green tea.[26]
- Sleep: Caffeine of green is responsible for a sleep disorder. The L-Theanine amino acid in green tea will increase your concentration and make you awake.[28] So don’t drink green tea before sleep.
Also read> Type, Nutrition Facts, Positive Effects and Health Benefits of Dates
Besides these green tea may increase bleeding time, risk of bladder cancer and block the absorption of thiamine.[26] So it is quite clear to us that green tea has both benefits and drawbacks. For this you need to be more concern about drinking it.
References:
[1] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2855614/
[2] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5824026/
[3] https://pubmed.ncbi.nlm.nih.gov/15585768/
[4] https://pubmed.ncbi.nlm.nih.gov/14519824/
[5] https://pubmed.ncbi.nlm.nih.gov/11209110/
[6] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2748751/
[7] https://www.webmd.com/heart-disease/news/20080702/green-tea-lowers-risk-of-heart-disease
[8] https://www.sciencedaily.com/releases/2018/05/180531190840.htm
[9] https://academic.oup.com/ajcn/article/94/2/601/4597944
[10] https://pubmed.ncbi.nlm.nih.gov/23803878/
[11] https://pubmed.ncbi.nlm.nih.gov/25242840/
[12] https://www.nature.com/articles/srep19710
[13] https://www.sciencedaily.com/releases/2019/09/190923101922.htm
[14] https://www.abc.net.au/science/articles/2010/04/20/2877864.htm
[15] https://www.nature.com/articles/sj.bdj.2010.436
[16] https://pubmed.ncbi.nlm.nih.gov/10926734/
[17] https://www.sciencedaily.com/releases/2003/04/030425071800.htm
[18] https://academic.oup.com/jn/article/141/6/1202/4600312
[19] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3123403/
[20] https://www.sciencedaily.com/releases/2011/06/110602143214.htm
[21] https://www.researchgate.net/publication/329680554_Green_tea_polyphenols_protect_neurons_against_Alzheimer’s_disease_and_Parkinson’s_disease
[22] https://www.huffpost.com/entry/anti-aging_n_5530751
[23] https://www.sciencedaily.com/releases/2016/02/160216181443.htm
[24] https://academic.oup.com/cdn/article/1/2/1/4558629
[25] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5093162/
[26] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3459493/
[27] https://www.sciencedaily.com/releases/2008/05/080515072944.htm
[28] https://www.healthline.com/nutrition/green-tea-before-bed
