Source: UNIVERSITY OF ARIZONA submitted to
EFFECTS OF GREEN TEA ON RESTING ENERGY EXPENDITURE, OXIDATIVE STRESS AND INFLAMMATION AMONG OVERWEIGHT POSTMENOPAUSAL WOMEN
 
PROJECT DIRECTOR: Thomson, C. A.
 
PERFORMING ORGANIZATION
NUTRITIONAL SCIENCES
UNIVERSITY OF ARIZONA
TUCSON,AZ 85721
 
NON TECHNICAL SUMMARY: Over 55%of post-menopausal women in America are overweight and many are resorting to unproven approaches to weight loss including green tea -based dietary supplements despite the fact that there is limited evidence of success and little is known about how green tea may work in the body to promote weight loss. This study is being conducted to determine if green tea can increase a person's metabolic rate and thus promote weight loss. Further we will evaluate if green tea can reduce oxidant stress on cells in the short-run and in turn have the potential to possibly change risk for chronic disease in the long run.
 
OBJECTIVES: 1. Recruit forty overweight, post-menopausal women for participation in the tea intervention trial. 2. Collect overnight urine samples (six collections total). 3. Measure resting energy expenditure (REE) before and repeatedly over a two hour interval following a single dose of green tea (two tea bags including a placebo tea or study green tea). 4. Measure methylated EGCG before and after each single dose of green tea corresponding in timing of measurement with collection of REE measurement. 5. Measure urinary catecholamine levels to determine if single dose of green tea with two tea bags per cup over 2-hr potentiates thermogenesis under sympathetic neural control. 6. Measure urinary F2-isoprostane and prostaglandin E2 metabolite (PGEM) levels to determine if six doses of green tea with two tea bags per cup over 48-hr will induce a significant rise in antioxidant and anti-inflammatory activity in the body. 7. Publish/disseminate research findings.
 
APPROACH: The effects of green tea on overweight postmenopausal women will be evaluated in a randomized, double-blinded, placebo-controlled, crossover design study. Overweight postmenopausal women with BMI between 25 and 35 will be recruited in this study. They will be randomized in a double-blind fashion to either a standardized green tea or placebo tea for the first study measures. Each intervention period will last for 48 hours. Study participants will adhere to a polyphenol free diet and keep food records throughout. Participants will collect six separate urine samples, pre and post tea 1 and pre and post tea 2. After the first tea dose, subjects will rest in a reclining chair for 30 minutes at which time their baseline REE will be measured. Participants will then drink the 1st dose of green tea (two tea bags with 360ml of boiling water cooled to room temperature) over a 10 minute period, and repeat measures of their REE will be taken at 30, 60, 90, 120 minutes after the single dose of tea consumption followed by urine sampling. Participants will then be asked to drink five more doses of tea in next 48 hours followed by urine sampling. Participants will then resume their daily routine for the next 5 days during which time they will continue on the polyphenol-free diet. After the wash-out period, above study procedures will be repeated with the alternate tea.
 
CRIS NUMBER: 0206749 SUBFILE: CRIS
PROJECT NUMBER: ARZT-136660-H-23-137 SPONSOR AGENCY: NIFA
PROJECT TYPE: HATCH PROJECT STATUS: TERMINATED MULTI-STATE PROJECT NUMBER: (N/A)
START DATE: Jul 1, 2006 TERMINATION DATE: Sep 30, 2010

GRANT PROGRAM: (N/A)
GRANT PROGRAM AREA: (N/A)

CLASSIFICATION
Knowledge Area (KA)Subject (S)Science (F)Objective (G)Percent
702223410105.1100%

CLASSIFICATION HEADINGS
KA702 - Requirements and Function of Nutrients and Other Food Components
S2234 - Tea
F1010 - Nutrition and metabolism
G5.1 - Ensure Access to Nutritious Food


RESEARCH EFFORT CATEGORIES
BASIC 15%
APPLIED 85%
DEVELOPMENTAL (N/A)%

KEYWORDS: green tea; energy expenditure; obesity; oxidative stress; inflammation

PROGRESS: Jan 1, 2009 TO Dec 31, 2009
OUTPUTS: By objective we have accomplished the following outputs: 1. Recruited forty overweight, post-menopausal women for participation in the tea intervention trial; also recruited 45 overweight breast cancer survivors into a 6 month green tea intervention of 4 c green tea vs placebo tea daily. 2. Collected overnight urine samples. 3. Measured resting energy expenditure (REE) before and repeatedly over a two hour interval following a single dose of green tea (two tea bags including a placebo tea or study green tea). 4. Measured urinary catecholamine levels to determine if single dose of green tea with two tea bags per cup over 2-hr potentiates thermogenesis under sympathetic neural control. 6. Measured urinary F2-isoprostane and prostaglandin E2 metabolite (PGEM) levels to determine if six doses of green tea with two tea bags per cup over 48-hr will induce a significant rise in antioxidant and anti-inflammatory activity in the body. 7. in the survivors measured several clinical, anthropometric and metabolic parameters pre and post 6 month green tea intervention. 8. completed analysis of available repeated measures cognitive testing in the breast cancer survivors participating in the GT intervention. These results were included in several breast cancer outreach presentations in Green Valley, Oro Valley and in an academic seminar in Nutritional Sciences at Purdue University (December 2009). The cognitive function research was published as an undergraduate Honor's Thesis in December 2009. PARTICIPANTS: Nicole Stendell-Hollis (pre-doctoral student in Nutritional Sciences) Jenna Fu (undergraduate in the Honor's thesis program) Others working on the project included: Ellen Cussler (statistical analysis), Emily Nardi (Staff dietitian) and Cynthia Thomson (PD). PARTICIPANTS: Partner organizations included Susan G Komen and Unilever Foods who provided tea product. Collaborators included faculty in biostatistics, psychology, Arizona Cancer Center. Training efforts include training of graduate students in laboratory techniques, training in dietary intervention trial methodology, training in human subjects research, training in biostatistics, peer-reviewed publication and professional research presentation. TARGET AUDIENCES: Target audiences include: 1) overweight breast cancer survivors 2) overweight adult females, 3)health care providers and 4) graduate students being educated in dietary intervention trial methodology. This year this research was central to J.Fu's Honor's Thesis and was presented at New Frontiers in Nutrition Sciences research symposium. This research was integrated into outreach presentations in diet and breast cancer presented at: Canyon Ranch Health Care Professional Rounds, Extension Services Training Program, AZ cancer Center High Risk Cancer Meeting and Oro valley Community Programming provided through the AZ Cancer Center. We also included health benefits of green tea for cancer in the American Cancer Society Eat Well, Be Well book that Dr Thomson co-authored this year (2010 publication date). PROJECT MODIFICATIONS: Nothing significant to report during this reporting period.

IMPACT: 2009-01-01 TO 2009-12-31 As previously reported, our results related to the short term green tea intervention and resting energy expenditure and catecholamines were published only in thesis form and suggested a modest 4% rise in REE with green tea intake for 2 hours post-consumption. Given these modest effects and our use of decaffeinated tea product we chose not to pursue this line of research inquiry further.In addition, no significant changes in cognitive function were demonstrated with green tea feeding and thus those results have not been widely disseminated. As for the 6 month green tea intervention in overweight breast cancer survivors, we have completed several clinical and metabolic measures in the past 2 years that suggest that while body weight was not significantly reduced as a result of green tea intervention, the metabolic profiles of these "at-risk" women improved significantly. Specifically we saw improvements in lipids, blood pressure and glucose. These results have been accepted for peer-review publication and as stated above have been disseminated to breast cancer survivors through Arizona Cancer Center sponsored community outreach programming.

PUBLICATION INFORMATION: 2009-01-01 TO 2009-12-31
Accepted with revisions: Stendell-Hollis N, Nardi E, Bea JW, Nardi E, Cussler E, Thomson C.(2010) Decaffeinated green tea intervention and changes in metabolic indices in overweight breast cancer survivors. Eur J Clin Nutr (in press).

PROJECT CONTACT INFORMATION
NAME: Thomson, C. A.
PHONE: 520-626-9294
FAX: 520-621-9446