Tea science stacks up for weight management, but concerns continue for extracts

Leaf through the scientific literature and the benefits of tea, green and black, for weight managements garner much support, but more research is needed before the beverage and its extracts have “great public health importance”, says a new review. On the other hand, researchers from Pennsylvania State University note that high-dose extracts may pose safety concerns, according to their timely assessment of the science to date in the Journal of Nutrition.

With the World Health Organization estimating that by 2015, there will be more than 1.5 billion overweight consumers, incurring health costs beyond $117 billion per year in the US alone, the opportunities for a scientifically-substantiated weight management food product are impressive. The market for food, beverage and supplement weight management products is already valued at $3.64bn (2009 figures) in the US, according to Euromonitor. In Western Europe, the market was worth $1.3bn in 2009.

Green tea has been studied extensively for its potential in the weight management category, with the compound epigallocatechin gallate (EGCG) highlighted as a key component. Three mechanisms have been proposed: EGCG could increase energy metabolism and fatty acid oxidation; inhibit fat cell development (apidogenesis); and/or reduce lipid absorption and increase fat excretion. It has also been reported that caffeine must also be present as, for EGCG to aid weight loss, a stimulated nervous system is needed. However, Dr Lambert said the underlying mechanism seems to be reduced absorption of dietary fat, although green tea may also stimulate energy expenditure. “The polyphenols seem to be the active components, but the interaction between tea poylphenols and caffeine has not been well-studied,” he said. Dr Josh Lambert, assistant professor in the Department of Food Science at Penn State told that laboratory studies and small-scale human intervention studies “indicate that consumption of tea might promote weight loss, help maintain body weight following weight loss, and prevent the development of some diseases associated with obesity such as diabetes and fatty liver disease”. “The effective doses seem to be 3 to 10 cups of green tea per day,” he added.

Green or black?

The health benefits of tea have been linked to the polyphenol content of the tea. Green tea contains between 30 and 40 per cent of water-extractable polyphenols, while black tea (green tea that has been oxidised by fermentation) contains between 3 and 10 per cent. The four primary polyphenols found in fresh tealeaves are epigallocatechin gallate (EGCG), epigallocatechin, epicatechin gallate, and epicatechin. “The majority of studies have been conducted using green tea, whereas a more limited number of have been conducted on black and Oolong teas,” wrote Lambert and Kimberly Grove. “Given the high prevalence of black tea consumption (80 per cent of worldwide tea consumption), further studies on the anti-obesity effects of this beverage could be of great public health importance.”

Unanswered questions and cause for concern

The reviewers raise concerns over green tea extracts, noting that high doses taken in the form of a supplement may cause toxicity. “These toxicities have not been widely observed in controlled human studies, but the case-reports and animal data suggest the need for further investigation and would indicate the need for caution in dose selection,” they said. For this reason, the reviewers noted questions remain unanswered regarding the therapeutic index when the tea compounds are consumed via the diet or taken as supplements, either as a pill or capsule. “Only with such a complete understanding can the potential benefits of dietary components with anti-obesity effects, including tea, be realized,” wrote Lambert and Grove.

Source: Journal of Nutrition Published online ahead of print, doi: 10.3945/jn.109.115972

“Laboratory, Epidemiological, and Human Intervention Studies Show That Tea (Camellia sinensis) May Be Useful in the Prevention of Obesity” Authors: K.A. Grove, J.D. Lambert

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Have you read the book? Or seen the movie?

PAY IT FORWARD is the story of a young boy who starts a chain reaction of goodness for his social studies project. His vision is simple: do a good deed for three people, and instead of expecting them to pay you back, ask them to pay it forward to three more people.

Is it possible for one idea to change the world? Yes, of course it is, even if in a small way.
The PAY IT FORWARD story reflects the inspiration behind TAO TI’s philosophy not just to be a sustainable business, but to make a difference in the lives of the people who drink our products, and to the wider community who have so much to benefit through better health. We are proud to do what we can to contribute to our vision of healthier communities.

At TAO TI we PAY IT FORWARD in a number of different ways…

Every bottle of TAO TI purchased contributes to THE BANK OF DREAMS Charity

  • We sponsor teams and groups that encourage healthy activity
  • We provide fundraising initiatives for your club or group
  • We partner with ESEBO in the vision of Turning Around Obesity

Would you like our help? Contact us with your request or ideas.

Find out about the Pay It Forward Movement.

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What are antioxidants? Here is the Wiktionary definition…

  1. Any substance that acts to slow or prevent the oxidation of another chemical.
  2. In nutrition, one of a group of vitamins that act against the effects of free radicals.

Antioxidants fight the free radicals that occur in our everyday lives.

Did you know that antioxidants have been shown to assist in reducing, reversing or preventing the following conditions?

TAO TI Green Tea has a very high level of polyphenol antioxidants - just 2 bottles of TAO TI per day will give you the same level of antioxidants used in clinical studies. We’re very proud that ours are all naturally occurring and captured within our authentic brewing process. No added antioxidant powders here!

If you’re fit and healthy now, keep it that way!!

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The ancient Chinese method of pan frying the tea leaves is used for Tao Ti Green Tea. This process enables quicker oxidization of the leaves and increases the amount of antioxidants better than any other process.

Boiling, steaming and extraction (which is used by other green tea products on the market) allows quicker production, and therefore greater volumes, but with less antioxidants and other health benefits.

Great taste!

Very simply, TAO TI tastes great! Kids and adults alike, love the fruit infused flavours of TAO TI Green Tea.

Other Benefits Bursting Forth from Green Tea


  • Ease and prevent indigestion, diarrhea and stomach pains.


  • Stimulates alpha brain waves and increases your brain's production of dopamine to give you an alert, yet relaxed, awareness
  • Reduces anxiety and enhances concentration and learning
  • Promotes a more restful sleep
  • Especially helpful for relaxing the mind
  • Regenerates damaged brain cells
  • Prevents cholesterol from turning bad through oxidation
  • Helps alleviate PMS symptoms
  • Neutralises the caffeine in tea naturally


  • Increase the body’s immunity against colds and flu


  • Inhibits the hardening and thickening of arteries
  • Reduces LDL cholesterol and triglycerides
  • Reduces fibrinogen, a protein involved in the formation of blood clots
  • Reduces the development of high blood pressure
  • Rehydrates as effectively as water, with additional health benefits
  • Naturally occurring fluoride strengthens tooth enamel against acids
  • Fights bacteria and viruses that cause throat infections, dental caries and other dental conditions, including bad breath

Supporting Evidence

"Drinking green tea is better for you than drinking water. Water is essentially replacing fluid. Tea replaces fluid and contains antioxidants, so it has two things going for it". 

- Dr Carrie Ruxton, Public Health Nutritionist at Kings College, London.

There is a wonderful range of other websites from around the world that can give you even more detail on research that has been done, and some of the seemingly miraculous results that individuals have achieved drinking green tea. Check them out, do your own research, and make your own decisions.

Here is one of our favourites…

Amazing Green Tea

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SteviaIt’s the latest buzz!

Stevia is a remarkable little herb, originally found growing in South America, and containing glycosides, which are 250 to 300 times sweeter than the sucrose in sugar.

Furthermore, the body does not metabolize the glycosides in Stevia, which results in a caloric intake of zero.

Stevia is not only sweeter than sugar, but it is also healthier. In Japan Stevia has been the number one sugar substitute for decades.

TAO TI is the first beverage company in New Zealand to have developed a drink sweetened with Stevia. Large players such as Coca-Cola and Pepsi have been trying to develop Stevia sweetened drinks for the past couple of years, but we have achieved the breakthrough in discovering how to achieve a superb flavour profile when using Stevia within our green teas.

We are also a leap ahead of competitors in using a natural source of Stevia rather than derivatives.

Stevia delivers zero carbohydrates, zero calories, and zero GI.

Find out more about Jim May, a pioneer of Stevia.

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