Black Tea
Metabolic Effects
A bioefficacy trial by Imran and colleagues[30] showed a reduction of LDL cholesterol and triglycerides and a significant increase in high-density lipoprotein cholesterol in rats administered black tea polyphenols (theaflavins and thearubigins). The study points to the potential for black tea polyphenols to alleviate hypercholesterolemia and hyperglycemia, with potential benefits in also combating diabetes.
Elevated homocysteine levels are believed to be associated with cardiovascular and cerebrovascular disease.[31] Zhu and colleagues[32] found a significant correlation between drinking black tea and hyperhomocycsteinemia in patients with hypertension. The effect was not found in people who drank oolong or green teas.
Ovarian Cancer
Black tea polyphenol (theaflavin-3,3'-digallate [TF3]) in combination with cisplatin has shown a synergistic cytotoxic effect on specific cisplatin-resistant human ovarian cancer cells, indicating that TF3 may have potential as an adjuvant for the treatment of advanced ovarian cancer.[33]
Neurodegenerative Disorders and Vascular Health
Isolated microbial metabolites (L-theanine, CDT-1, and CDT-2) extracted from dark tea helped decrease age-related neurodegenerative disorders in mice.[34]
A long-standing debate about milk and tea is not just about whether the milk should be added to the cup first or vice versa. More than a decade ago, a small study suggested that adding milk to black tea negates the vascular benefits of tea, probably by promoting the formation of complexes with tea catechins.[35] In a small recent study, Ahmad and colleagues[36] also found that adding milk to black tea alters the favorable impact of tea consumption on vascular function and blood pressure—for as-yet unknown reasons.
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Cite this: Drinking Tea: Are the Health Benefits Real? - Medscape - Jan 17, 2019.
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