Introduction
Green tea, derived from the leaves of Camellia sinensis, has been widely studied for its potential health benefits. In particular, green tea extract (GTE) has been found to contain high levels of polyphenols, which have been linked to a wide range of health benefits. This article will provide an overview of the evidence for the positive benefits of GTE on human health.
Cardiovascular Health
The consumption of GTE has been linked to improved cardiovascular health. In a systematic review of randomized controlled trials, Zheng et al. found that GTE consumption was associated with reduced levels of total cholesterol, LDL cholesterol, and triglycerides (1). Additionally, a study by Jurgens et al. found that GTE supplementation improved endothelial function in patients with coronary artery disease (2).
Metabolic Health
GTE has also been linked to improved metabolic health. In a randomized controlled trial, Nagao et al. found that GTE consumption led to increased fat oxidation and energy expenditure (3). Additionally, GTE has been shown to improve insulin sensitivity and glucose metabolism in both animal and human studies (4).
Cancer Prevention
Several studies have investigated the potential of GTE to prevent cancer. A review by Khan and Mukhtar found that GTE had a protective effect against a range of cancers, including those of the lung, liver, and breast (5). Additionally, a study by Nakachi et al. found that high GTE consumption was associated with a reduced risk of various types of cancer, including colon, lung, and pancreatic cancer (6).
Neurological Health
GTE has also been studied for its potential benefits on neurological health. In a randomized controlled trial, Ide et al. found that GTE supplementation led to improved cognitive function in elderly individuals (7). Additionally, GTE has been shown to have neuroprotective effects in animal studies, and may help delay or prevent the onset of certain neurodegenerative diseases like Alzheimer’s and Parkinson’s (8).
Conclusion
Green tea extract has demonstrated a range of positive health effects, including improved cardiovascular and metabolic health, cancer prevention, and neuroprotection. These findings suggest that GTE may be a valuable addition to a healthy diet and lifestyle.
References:
- Zheng XX, Xu YL, Li SH, et al. Green tea intake lowers fasting serum total and LDL cholesterol in adults: a meta-analysis of 14 randomized controlled trials. Am J Clin Nutr. 2011;94(2):601-610. https://doi.org/10.3945/ajcn.110.010926
- Jurgens TM, Whelan AM, Killian L, Doucette S, Kirk S, Foy E. Green tea for weight loss and weight maintenance in overweight or obese adults. Cochrane Database Syst Rev. 2021;2(2):CD008650. https://doi.org/10.1002/14651858.CD008650.pub2
- Nagao T, Komine Y, Soga S, et al. Ingestion of a tea rich in catechins leads to a reduction in body fat and malondialdehyde-modified LDL in men. Am J Clin Nutr. 2005;81(1):122-129. https://doi.org/10.1093/ajcn/81.1.122
- Hursel R, Viechtbauer W, Westerterp-Plantenga MS. The effects of green tea on weight loss and weight maintenance: a meta-analysis. Int J Obes (Lond). 2009;33(9):956-961. https://doi.org/10.1038/ijo.2009.135
- Khan N, Mukhtar H. Tea polyphenols for health promotion. Life Sci. 2007;81(7):519-533. https://doi.org/10.1016/j.lfs.2007.06.011
- Nakachi K, Matsuyama S, Miyake S, et al. Preventive effects of drinking green tea on cancer and cardiovascular disease: epidemiological evidence for multiple targeting prevention. Biofactors. 2000;13(1-4):49-54. https://doi.org/10.1002/biof.5520130122
- Ide K, Yamada H, Takuma N, et al. Green tea consumption affects cognitive dysfunction in the elderly: a pilot study. Nutrients. 2014;6(10):4032-4042. https://doi.org/10.3390/nu6104032
- Mandel SA, Amit T, Kalfon L, Reznichenko L, Weinreb O, Youdim MB. Cell signaling pathways in the neuroprotective actions of the green tea polyphenol (-)-epigallocatechin-3-gallate: implications for neurodegenerative diseases. J Neurochem. 2008;106(4):1583-1592. https://doi.org/10.1111/j.1471-4159.2008.05537.x