Which tea is better for blood vessels?
Last reviewed: 12.03.2022
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There is an opinion that green tea is healthier than black tea. But, as it turned out, it is black tea that can inhibit the processes of oxidative stress in the aorta in patients after radiation therapy.
The benefits of green tea are due mainly to the presence of plant polyphenols in it, which significantly reduce the risk of damage to the cardiovascular system in individuals predisposed to such diseases. In addition, polyphenols relieve the symptoms of atherosclerotic manifestations , have a positive effect on cellular structures. But such plant components are present in both green and black tea. Therefore, it is certainly difficult to say which of the drinks is healthier. Representatives of the Institute of Biophysical Theory and Experiments tried to understand this issue. According to the results of the work, they concluded that black tea is more useful for blood vessels.
The scientists compared how both drinks are able to block the development of oxidative stress inside the aorta after exposure to radiation exposure. What are oxidative stress processes? We are talking about an increase in the number of active oxygen variations, aggressive oxidative molecules that affect the course of various intracellular reactions. In previous studies, experts have found that radiation exposure as part of radiation therapy activates ACE (angiotensin-converting enzyme), which is of great importance in regulating blood pressure. However, due to ACE hyperactivity, there is an increase in active oxygen variations: in particular, they can increase the risk of developing atherosclerotic changes in the vessels.
Scientists conducted experimental studies on rodents. Rats were offered tea of varying degrees of saturation, after which they were exposed to radioactive irradiation. Next, the degree of angiotensin-converting enzyme activity was measured, as well as the number of active oxygen variations inside the aorta. The experiment showed that drinking tea lowered both the active position of ACE and the number of oxidative molecules. Remarkably, the black drink was more effective than the green one. A much smaller amount of black tea was required to completely suppress intra-aortic oxidative stress, and the effectiveness became noticeable much earlier.
Scientists note that the composition of green tea does contain many useful substances that can independently trigger the processes of oxidative stress. However, black tea has a more pronounced effect in this situation.
It is likely that with the help of a well-known and familiar drink, it is possible to block the processes of intravascular oxidative stress. Such stress becomes inevitable for patients undergoing radiotherapy treatment of malignant tumors, because radiation also affects healthy tissue. In the future, experts intend to study the polyphenolic components of tea separately from each other, compare their activity and the degree of influence on oxidative reactions in the vessels.
Full details of the study are available on the ScienceDirect page.