[PDF] Tea Polyphenols in Promotion of Human Health | Semantic Scholar (2024)

Study provide strong evidence that owing to antioxidant properties daily intake of green tea may be used as a preventive measure for different types of cancer and other diseases.

How catechins affect the survival, proliferation, invasion, angiogenesis, and metastasis of tumors by modulating cellular pathways is focused on.

The results showed that the IC50 (mg/ml, weight/volume) of both tea types were inversely proportional to their polyphenol content, suggesting a relationship between toxicity andpolyphenol levels in both green and black tea.

Tea and coffee are consumed worldwide and epidemiological and clinical studies have shown their health beneficial effects, including anti-cancer effects, but human studies are still controversial and some studies have suggested even an increased risk for certain types of cancers with green tea consumption and bladder and lung cancers with coffee consumption.

Overall, green tea has been found to be effective to reduce the risks of breast cancer, ovarian cancer, liver cancer, colorectal cancer, skin cancer, prostate cancer, oral cancer, etc, however, sufficient information was not found to support that green tea consumption reduces the risk of lung cancer, esophageal cancers, or stomach cancer.

The characteristic variation of GTs, WTs, and Fl of two tea varieties are shown and may support crop quality improvement and promote the valorization of tea Fl.

Overall, tea possesses prebiotic-like effect and can alleviate the gut microbiota dysbiosis induced by high-fat diet in gut microbiota, despite the detailed bacterial taxa may alter depending on the types of tea supplemented.

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It is the aim of this chapter to raise some of the unanswered questions regarding cancer prevention by tea and to stimulate further research in this area.

There is insufficient and conflicting evidence to give any firm recommendations regarding green tea consumption for cancer prevention, and drinking green tea appears to be safe at moderate, regular and habitual use.

The potential health benefits of dietary polyphenols from the point of view of bioavailability are discussed and tea catechins, curcumin, and proanthocyanidins are used as examples to illustrate some of the problems that need to be resolved.

Tea has received a great deal of attention because tea polyphenols are strong antioxidants, and tea preparations have inhibitory activity against tumorigenesis, but epidemiological studies have not yielded clear conclusions concerning the protective effects of tea consumption against cancer formation in humans.

PCA risk among Chinese men in Hong Kong was inversely associated with green tea consumption and EGCG intake, but these results need to be replicated in larger studies.

There is considerable evidence that tea polyphenols, in particular (−)-epigallocatechin-3-gallate, inhibit enzyme activities and signal transduction pathways, resulting in the suppression of cell proliferation and enhancement of apoptosis, as well as the inhibition of cell invasion, angiogenesis and metastasis.

The findings of various in vitro, in vivo and human studies signifying the chemopreventive effects of tea polyphenols against UVB‐induced skin cancer are discussed.

An extensive analysis of the key findings from studies on the effects of dietary antioxidants such as tea polyphenols, curcumin, genistein, resveratrol, lycopene, pomegranate, and lupeol against cancers of the skin, prostate, breast, lung, and liver is presented.

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