Benefits of Tea highlighted

Research reveals that tea provides more flavonoid antioxidants than any other food or beverage in the U.S. diet.

25/10/05 Research presented at the American Dietetic Association's (ADA) annual meeting revealed that tea provides more flavonoid antioxidants than any other food or beverage in the U.S. diet.

Other studies presented at the conference indicated that tea flavonoid antioxidants might provide a myriad of health benefits, including reduced risk for heart disease, control of metabolic syndrome and blood glucose regulation as well as emerging neuroprotective effects.
"Several studies have found that drinking tea may be good for the heart due to power of flavonoid antioxidants - the antioxidants found in tea," said Douglas Balentine, Ph.D., Director Nutrition Sciences North America, who presented at the ADA Food and Nutrition Conference & Expo about the role of dietary flavonoids in health.  "For most Americans, drinking a cup of tea a day - hot or cold, black or green - will nearly double their current intake of flavonoid antioxidants."

In a presentation titled "Potential Health Benefits of Dietary Flavonoids" Balentine presented the latest findings about tea consumption and human health.  Here are highlights from the presentation:

Antioxidants are known to help protect the body from the damaging effects of free radicals.  Damage caused by free radicals contributes to aging and cardiovascular disease.  Flavonoids are a type of antioxidant that are known to be biologically active and are found primarily in plant-based foods and beverages, including fruits and vegetables, chocolate, red wine and regular tea.  Tea, the primary source of flavonoid antioxidants in the U.S. diet, contains approximately 125 mg flavonoids per cup (225ml).

Populations with higher intakes of dietary flavonoids have a reduced risk of developing cardiovascular disease.  Clinical and mechanistic studies have demonstrated that dietary flavonoids, especially the catechin class, may help improve cardiovascular health by improving endothelial function, reducing inflammation in the vascular endothelium, and by reducing platelet activity.

A recent analysis of the Nurses Health Cohort found that tea drinkers have a lower risk of developing type 2 diabetes. Emerging evidence suggests that flavonoids may also play a role in maintaining blood sugar levels and improves insulin sensitivity.

Using data from the national nutrition monitoring surveys (CFSIII) and the USDA Database describing the flavonoid content of foods, a research team from Exponent, a scientific research firm, found that the average flavonoid intake of U.S. consumers is 134.0 mg/day.  Beverages were found to be the major contributors of dietary flavonoids in this study, with an average of 125.0 mg/day.  Tea was found to provide 117mg/day of dietary flavonoids or 87 percent of the dietary flavonoids in the U.S. diet. The data presented by Exponent adds to similar data presented earlier this year from Michigan State University researchers, who also found tea to be the leading source of flavonoid antioxidants in the U.S. diet.

New research conducted at the Unilever Food Research Centre in Vlaardingen, The Netherlands and the University of Nottingham in Nottingham, U.K. used nutritional metabonomics to determine whether green and black teas are metabolically equal.  The study included 14 healthy males who were given a daily dose of equal amounts of green tea solids, black tea solids or 360 mg caffeine (control) in a randomized crossover design study.  Metabonomics is a new research technique that uses complex modeling to assess metabolic effects of dietary interventions in the body.  The study found that black and green tea resulted in a comparable increase in the urinary excretion of flavonoid metabolites.

Recent research reported in the September issue of The Journal of Neuroscience found that green tea catechin EGCG, was capable of reducing biomarkers linked to Alzheimer's disease in animal models.  Alzheimer's disease is one of several neurodegenerative diseases that is thought to be linked to free radicals and ensuing inflammation and impaired blood flow to the brain and surrounding tissues.  Research shows that oxidative stress from the daily effects of living, normal metabolism, exercise and environmental pollutants and toxins such as sunlight and carbon monoxide result in the production of free radicals.  Other studies show that diets or dietary compounds that help improve blood flow and heart health, such as antioxidants found in green or black tea, may also promote good blood flow to the brain and nervous system.  A research team in Israel found that EGCG, a flavonoid found in both black and green teas, is effective in blocking damage to nerve cells in models of Alzheimer's and Parkinson's Disease.

Together, the new tea research presented by Balentine adds to many existing studies that indicate drinking tea regularly is healthful, and it may help reduce risk for many chronic, degenerative diseases.  For optimal health benefits, tea should be consumed as part of a balanced diet containing a wide variety of fruits, vegetables and whole-grain products.

Lipton(R) Teas, made from real tea leaves, feature the AOX(TM) Seal, a proprietary mark that indicates a substantial level of antioxidants. Certified by the Unilever Health Institute in The Netherlands, the AOX(TM) Seal is unique to Lipton(R) products and can be found on many green and black teas, including tea bags, Green Tea Iced Tea Mix, Lipton To Go and most ready- to-drink bottled iced teas.

The American Dietetic Association provides the oversight and professional accreditation to nearly 65,000 registered dietitians and dietetic technicians. The ADA is the nation's largest organization of food and nutrition professionals in the United States. ADA serves the public by promoting optimal nutrition, health and well being.  At the ADA's FNCE annual meeting, the media and the food industry together address critical food and nutrition issues that impact consumers.