When a study in her lab showed that mate (mah’ tā) tea drinkers had experienced a significant increase in the activity of an enzyme that promotes HDL (good) cholesterol while lowering LDL (bad) cholesterol, University of Illinois scientist Elvira de Mejia headed for Argentina where mate tea has been grown and taken medicinally for centuries.

She returned with a five-year agreement signed by administrators of La Universidad Nacional de Misiones (UNaM) to cooperate in the study of 84 genotypes of mate tea, both cultivated and wild, never-before-studied, varieties. The arrangement calls for the writing of joint grants and an exchange of students and professors between UNaM and the U of I.

The scientist is also negotiating a grant from the National Institute of Yerba Mate to fund further research, she said.

“Our studies show that some of the most important antioxidant enzymes in the body are induced by this herbal tea,” said de Mejia of her study in September’s Planta Medica.

“Because Argentina has the different mate varieties, we’ll be able to do more comparisons and characterizations between the different genotypes and the benefits of different growing conditions—whether in sun (on a plantation) or in shade (under the rainforest canopy),” she added.

Not only does de Mejia hope to identify the most nutritionally beneficial genotypes of the herbal tea, she hopes that Argentine experience with drying and processing mate will lead to improved extraction of the tea’s bioactive compounds. “Food companies are very interested in adding tea extracts to juices, soda, and even beer to increase the nutritional value of their products,” she said.

In the cholesterol study, blood levels of the cardio-protective enzyme paraoxonase-1 were measured before and after healthy volunteers consumed either 0.5 liters of mate tea, milk, or coffee. Activity of the enzyme increased an average of 10 percent for mate tea drinkers compared to the other drinks.

“The tea used in the study was prepared at the same concentration used in South America, although they usually drink 2 to 3 liters per day,” said de Mejia.

In South America, mate is usually drunk from a dried gourd and consumed through a metal straw. About 50 grams of dry leaves are packed into the gourd and hot water is poured over them; this is repeated many times, with as much as ½ to 1 liter of water. This method of consumption allows tea drinkers to slowly extract the antioxidants and polyphenols before they can be oxidized.

“To duplicate these results with mate teabags, you would need to use four or five teabags instead of one. It’s a strong taste, but many people say that coffee has a strong, bitter taste. This is more of a grassy herbal taste. It may be an acquired taste, but I seem to have acquired it,” said graduate student Caleb Heck who accompanied de Mejia to Argentina.

Heck characterized the tea consumed in the cholesterol study in de Mejia’s U of I labs and is now working with the tea brought back from Argentina. He said that mate is high in xanthines (mainly caffeine), and he has found 12 polyphenolic compounds at different concentrations, depending on where the tea was grown. Polyphenols are thought to have a protective effect against cancer and cardiovascular disease.

He is quickly becoming something of an authority on the subject, and he and de Mejia have written a comprehensive review of mate tea, including its chemistry, health implications, and the technological considerations involved in its processing, that has been published in November’s Journal of Food Science, which can be viewed at http://www.blackwell-synergy.com/toc/jfds/0/0. The study was funded by the University of Illinois Research Board.

Heck and de Mejia of the U of I and Teresita Menini and Alejandro Gugliucci of Touro University co-authored the study of the effect of mate tea on HDL cholesterol, which appears in the September issue of Planta Medica. The study was funded by the University of Illinois Research Board and Touro University.

Green tea is used by the Chinese as a traditional medicine to treat many ailments including acne and to improve general well-being. But does it provide an effective herbal alternative to modern medication?
The answer seems to be ‘Yes’.  There are only two herbal treatments that are known to be effective in treating acne and green tea is one of them.
In a recent study by Jennifer Gan-Wong, M.D. a green tea cream was trailed against a 4% benzoyl peroxide solution on people suffering with moderate to severe acne. The results from this research study showed that green tea was just as good in treating acne as the benzoyl peroxide.
But benzoyl peroxide dries out skin causing itching or allergic reactions. Unlike green tea that has the added advantages of natural anti-bacterial properties and antioxidants, particularly epigallocatechin gallate which is 200 times more powerful than vitamin E at fighting free radicals.
Green tea also helps to reduce inflammation, hormonal activity and aids in detoxification - which is all good news for acne sufferers.
Green tea extract is an extremely versatile herbal supplement - it can be administered topically, often being used in creams, taken as a in the form of a pill or incorporated into your diet and drunk as a tea.
This last method is very popular (Green Tea with Honeysuckle is often known as ‘Pimple Tea’ in many Chinatowns) when drunk after a meal it aids digestion and helps to detoxify your system, getting rid of the toxins that can cause acne. Tip: don’t drink it with sugar, this will neutralize the worthwhile effects of the tea.
It seems that taking green tea for acne is a win-win situation… It has many beneficial properties which promote good all-round health with little or no known side effects and for the price, it’s definitely a herbal treatment that’s worth trying.

16/10/2007 - Tea, seemingly always in the headlines for its potential health benefits, could also offer an interesting source of food preservatives, Chinese researchers report.

Extracts from microbially-fermented Puer tea and Fuzhuan brick-tea have the potential to inhibit several food-borne bacteria, including Bacillus cereus, Bacillus subtilis, Clostridium perfringens and Clostridium sporogenes.
 

“With the trend of increasing use of natural and biological preservatives in food products, natural antimicrobial agents from microbial fermented tea may offer an innovative and interesting measure for such applications,” wrote lead author Haizhen Mo from Henan Institute of Science and Technology.

Before such a resource can be tapped however the researchers state that several critical aspects still need to be clarified before the tea extracts can be industrialised as alternatives to synthetic preservatives such as like butylhydroxyanisole (BHA) and butylhydroxytoluene (BHT) to slow down the oxidative deterioration of food.

Suspicion over chemical-derived synthetic preservatives has pushed food makers to source natural preservatives such as rosemary extract instead, and market analysts Global Information pitch the global food preservative market at €422.7bn ($575bn), reaching €522bn ($710bn) by 2008.

Among the challenges left include identification of the exact components in the tea responsible for the antimicrobial effects. Indeed, Mo and co-authors ask whether it is the more well-known tea catechins or polyphenols or antimicrobial metabolites from the fermentation process not originally present in unfermented or green tea leaves that are responsible.

Another area in need of research is whether the antimicrobials could impact the flavour and nutritional aspects of the food products.

“These natural preservatives should be desirably colourless and tasteless so that they will not bring about any off flavour troubles,” wrote the researchers.

“Ideally, these natural preservatives should not bring about any anti-nutritional effects,” they added.

The process for fermentation also needs optimising, they said.

“[Both] Puer tea and Fuzhuan brick-tea… are produced through a solid state fermentation process, [and] standardisation and optimisation are necessary. Solid-state fermentation is described as a process where no free water is present.

“A standardised fermentation process will not only ensure food safety but also the product quality.

“Furthermore, during the standardisation and optimisation of the process, more insight will be obtained for the metabolic mechanism of the fungi involved, how they produce antimicrobial metabolites and eventually an overproduction of these useful natural preservatives can be expected,” they concluded.

The study was a collaboration with researchers from Wageningen University and Research Centre in the Netherlands and the Chinese Academy of Agricultural Sciences.

Source: Trends in Food Science & Technology (Elsevier)
Published on-line ahead of print, doi: 10.1016/j.tifs.2007.10.001
“Microbial fermented tea - a potential source of natural food preservatives”
Authors: H. Mo, Y. Zhu, Z. Chen

The Canadian Press

TORONTO — New scientific research suggests that drinking tea may lower an individual’s risk of developing dementia and other neurodegenerative disorders such as Parkinson’s and Alzheimer’s diseases.

This data and other new research that suggests drinking tea may improve and maintain brain health and function was presented at the recent Fourth International Scientific Symposium on Tea and Human Health in Washington, D.C.

The body of research shows that tea likely directly impacts brain health by maintaining brain cell function and by assisting in the repair of damaged cells, says Carol Greenwood, a professor of nutritional sciences at the University of Toronto.

“Drinking tea may further help because it reduces the risk of developing other disorders which increase the risk of cognitive decline and dementia,'’ she says.

The latest findings on other potential health benefits of tea, including how it may play a role in shifting metabolism to favour weight loss and better manage sugar levels, were also unveiled at the symposium in September.

As well, other new studies that add to the existing body of knowledge about tea’s potential ability to reduce risk for several chronic diseases were presented.

“These include research that show flavonoids present in tea may improve cardiovascular health by reducing inflammation which are diseases and disorders that increase the risk of dementia,'’ says Greenwood.

Flavonoids are compounds found in fruits, vegetables, tea, coffee, beer, wine and fruit drinks. They have created considerable interest because of their potential beneficial effects on human health.

“Tea’s potential role in helping to maintain healthy body weight may also help prevent dementia,'’ Greenwood adds, “because most of the diseases and disorders associated with the risk of cognitive decline and dementia are more prevalent among those who are obese which haven’t been well communicated.'’

Greenwood says that although green tea was used in the research rather than black, “if you look at the two beverages it is the same leaf from the same plant.

“It is just dried a little differently. The green leaf is dried more rapidly than the black and if it dries slowly it browns and that is effectively what the black tea is going through.'’

Consequently, she says, data shows that there is no difference in the strength of flavonoids between green and black tea.

Greenwood says despite concerns that adding milk to tea would dissipate the amount of flavonoids, “we are in an ambiguous situation at this point in which there are two studies showing that might be the case and two studies suggesting that it’s not.'’

“From my perspective, if you look at the amount of flavonoids you actually get in a cup of tea it is so much more than any other food,'’ she says. “A lot of what we are tasting in the tea are themselves the flavonoids. So the stronger the brew, the more flavonoids are going to be there.'’

It would appear that Canadians drink a lot of tea — seven billion cups each year. In 2006, the tea market in Canada was worth approximately $319 million, reports the Tea Association of Canada.

A new study found that older women who are regular tea drinkers may be helping to keep their bones strong.

The Australian study involved 1,500 women over a period of five years. 

Researchers found that elderly women who drank tea had a higher bone density and did not lose as much mineral density from the bones in their hips as non-tea drinkers.

Antioxidants in the tea may play a role in the findings, according to researchers.