Black Tea, What It Is
Black tea is a special variety of tea that is far more oxidized than the other green tea, oolong tea and white tea varieties of tea.
Loose Leaf Black Tea
All four varieties are cultivated from leaves of the Camellia sinensis plant. Black tea is stronger in flavor and contains more caffeine than less oxidized teas.
In China and culturally influenced countries, black tea is known as “crimson tea” (紅茶, Mandarin Chinese hóngchá; Japanese kōcha; Korean hongcha), an even more accurate description of the color of the liquid. The name black tea, however, could also alternatively be in reference to the color of the oxidized leaves. In China, “black tea” is a commonly used classification for post-fermented teas, such as Pu-erh tea. However, in the Western world, “red tea” more commonly refers to rooibos, a South African tisane.
Efficacy of a green tea extract rich in catechin polyphenols and caffeine in increasing 24-h energy expenditure and fat oxidation in humans.
Background: Current interest in the role of functional foods in weight control has focused on plant ingredients capable of interfering with the sympathoadrenal system.
Objective: We investigated whether a green tea extract , by virtue of its high content of caffeine and catechin polyphenols, could increase 24-h energy expenditure (EE) and fat oxidation in humans.
Design: Twenty-four-hour EE, the respiratory quotient (RQ), and the urinary excretion of nitrogen and catecholamines were measured in a respiratory chamber in 10 healthy men. On 3 separate occasions, subjects were randomly assigned among 3 treatments: green tea extract (50 mg caffeine and 90 mg epigallocatechin gallate), caffeine (50 mg), and placebo, which they ingested at breakfast, lunch, and dinner.
Results: Relative to placebo, treatment with the green tea extract resulted in a significant increase in 24-h EE (4%; P<0.01) and a significant decrease in 24-h RQ (from 0.88 to 0.85; P<0.01) without any change in urinary nitrogen. Twenty-four-hour urinary norepinephrine excretion was higher during treatment with the green tea than with the placebo (40%, P<0.05). Treatment with caffeine in amounts equivalent to those found in the green tea extract had no effect on EE and RQ nor on urinary nitrogen or catecholamines.
Conclusions: Green tea has thermogenic properties and promotes fat oxidation beyond that explained by its caffeine content per se. The green tea extract may play a role in the control of body composition via sympathetic activation of thermogenesis, fat oxidation, or both.
American Journal of Clinical Nutrition 70:1040-1045
Dulloo, A. G., C. Duret, D. Rohrer, L. Girardier, N. Mensi, M. Fathi, P. Chantre, and J. Vandermander (1999)
Anti Oxidants, What They Are
We’re positive you’ve heard of antioxidants. It’s the new buzz word these days and dozens of new products are being made, promoting all the benefits of anti-oxidants from foods to beverages and even skin care too! Why are antioxidants so important to us?
AntiOxidant Chart
To make it simple, anti-oxidants fight free radicals or rather repair the damage free radicals have on our body. Free radicals which exist in the environment (there is nothing we can do about that) are what cause oxidative damage to our cells. Free radicals are cause everything from pre-mature aging to many diseases. What happens is called oxidation of the body’s cells, and when you include a diet rich in anti-oxidants, they repair some of this damage.
Numerous studies have been performed on the benefits of a diet high in antioxidants. Although quite a few studies state more research is needed (and occuring), with all the potential benefits, why not include antioxidants into your diet?
