A healthy drink, black or green

Tag : black & green

BLACK tea helps in mental alertness and ability to focus, whilegreen tea catechins may play a part in reducing fat deposits aroundvital organs, the Lipton Tea Institute revealed recently.
In a Tea Science Symposium 2008 organised by the tea purveyor lastweek, experts unveiled new evidence of the benefits of black teaand green tea.
Jane Rycroft, beverages global nutrition manager for Unilever, saidthat studies have shown that black tea consumption has a positiveeffect on your levels of alertness during the day.
The key ingredient is said to be an amino acid called L-theanine, anatural component found almost exclusively in tea. Each cup ofblack tea naturally contains five mg to 23 mg of L-theanine,depending on the blend and brewing method.
About 10 years ago, Japanese researchers discovered that 200 mg ofL-theanine increases alpha brain waves, which are associated with arelaxed yet alert mental state during rest.
To further investigate this, Unilever commissioned OxfordUniversity to conduct a series of EEG (electroencephalography:measurement of electrical activity produced by the brain asrecorded from electrodes placed on the scalp) studies withL-theanine in healthy volunteers.
The studies confirmed that 50 mg L-theanine (found in a few cups oftea, such as Lipton's Yellow Label tea, as the company pointed out)increases alpha brain activity gradually over time, with apparenteffect after 80 minutes of drinking the theanine and still apparent105 minutes later.
Emerging research also suggests that L-theanine may play a role inthe ability to focus attention. Recent research has shown thatthere is a very specific pattern of alpha activity when humansfocus their attention on information coming from a variety ofsensory stimuli. This is known as the alpha attention effect.
The study showed that 250 mg L-theanine improves attention-relatedalpha activity, which may enable individuals to focus attentionmore effectively. Given this evidence, scientists from the LiptonInstitute of Tea have shown that two to three cups of tea can helpyou focus and they believe this is due to theanine combined withthe other benefits of tea.
As for green tea, catechins have been the recent focus as evidencepoints towards their effects on body composition and fatdistribution. Catechins are a large group of very active flavonoidsfound in high quantities in green tea.
According to Niels Boon, a research scientist at Unilever Food andHealth Research Institute who also spoke at the symposium, recentstudies have shown that consumption of catechin-enriched green teahas repeatedly shown it to be an effective treatment in reducingvisceral obesity (excessive deposition of fat around the organs) inAsians.
The combined effects of catechins and caffeine in green tea couldtrigger increased energy expenditure in the body. Studies haveshown that visceral obesity is linked to increased risks indiabetes and cardiovascular diseases.
In a clinical trial conducted by Unilever in Shanghai, volunteerswere asked to consume daily either a placebo, one serving ofcatechin-enriched green tea (ie, 470 mg/day) or two servings of thebeverage (total catechins: 940 mg/day) for eight weeks. The resultsshowed that one serving of the catechin-enriched green tea hadhelped to reduce body weight by almost one kg and waistcircumference by 1.8 cm in eight weeks.
If taken longer, 90 days for instance, the more green tea taken,the greater the effect. Those who took two servings of a 440catechin beverage a day for 90 days saw body weight reduced by 1.2kg, waist circumference reduced by two cm, and the amount ofvisceral fat reduced by almost 6 per cent.
This indicates that there is a correlation between dosage andresult over a longer period of consumption. So far, researchsuggests that long-term consumption of catechin-rich green tea hasstronger effects on body composition and fat distribution than bodyweight in Asian populations.
Emphasising the value of drinking tea, Aart Jan Van Triest,vice-president of brand development beverages-Asia, Unilever, said:'The life we lead today is much more busy and stressful than thoseof our parents. It becomes harder to make time to lead healthierlives. For many of us, drinking tea is already a daily habit -knowing that you are already on to a good thing may encourage youto include other healthy habits as part of your daily life.'
This story was first published in The Business Times on July 12,2008.