Study: Tea and Vascular Health

Tea has been studied for many health benefits—from cognitive function to ovarian cancer, and now, vascular function. A new study published in Nutrients found theaflavins, which are unique to black tea, as they are formed from catechins during the enzymatic oxidation of tea leaves, could improve vascular function (2014;6(12):5772-85).

Beneficial effects of flavonoid-rich black and green tea on macrocirculation have been well-established, but researchers wanted to gain more insight into the effects of theaflavins on microcirculation and to compare effects with another important flavonoid class: the green tea-derived catechins, which have been reported to improve vascular function.

Twenty-four healthy subjects were included in the double blind, placebo-controlled, randomized, crossover study. On six different days, subjects received capsules with a single dose of catechins (500 mg), four varying doses of theaflavins (100 to 500 mg) or placebo. Microcirculation was assessed after each treatment by Pulse Amplitude Tonometry (EndoPAT) at baseline and two, four and six hours after test product intake.

The EndoPAT reactive hyperemia response was improved by 500 mg catechins and by 500 mg theaflavins compared to placebo. Also, 300 mg theaflavins increased the reactive hyperemia index, but no effects were observed at lower doses. The study results suggest moderate effects of single doses of catechins and theaflavins on peripheral microcirculation.

The ready-to-drink beverage market features a wide range of products, which includes both tea and coffee. Moreover, tea and coffee have shown tremendous growth in the RTD category. A since beverages are by far the category that utilizes functional ingredients the most, its no surprise that beverage formulators are using tea, mainly green tea extract, and coffee for their caffeine content in sports/energy drinks, too. Tea and coffee shots are gaining popularity as well, as consumers like on-the-go, easy-to-take beverages.