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Long-term Effects of Green Tea on Gut Flora, Fat Absorption, Body Composition and Resting Energy Expenditure

Long-term Effects of Green Tea on Gut Flora, Fat Absorption, Body Composition and Resting Energy Expenditure

Status
Completed
Phases
NA
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT01556321
Enrollment
70
Registered
2012-03-16
Start date
2012-06-30
Completion date
2015-04-30
Last updated
2016-03-18

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Obesity

Keywords

Obesity, Body weight, Gut flora, Fat absorption

Brief summary

Green tea may have positive effects for weight control and on body composition via several approaches such as a positive effect on the gut flora, a decrease in fat absorption from the intestines and an increase in resting energy expenditure.

Detailed description

Green tea may have positive effects for weight control and on body composition via several approaches such as a positive effect on the gut flora, a decrease in fat absorption from the intestines and an increase in resting energy expenditure. We would like to investigate the long-term effects of green tea on gut flora, fat absorption, resting energy expenditure and body composition. The study will be conducted in a randomized, placebo-controlled, double-blind parallel design with four groups consisting of control groups and green tea groups with normal weight subjects and obese subjects. At three time points (baseline, 6 weeks and 12 weeks) faeces are collected for analyzing the gut flora composition and fat content. Furthermore, measurements of resting energy expenditure and body composition will be conducted. Activity will be measured during three weeks (baseline, week 6 and week 12). a hundred healthy subjects (50 males and 50 females) with a BMI between 18.5-25 kg/m2 and ≥30 kg/m2 and aged between 18-50 years will be included in the study. All subjects will be non-smoking, non tea-drinkers, weight stable, dietary unrestraint, and at most moderate alcohol and caffeine consumers. Subjects will be free of medication except for oral contraceptives use in women. Intervention (if applicable): Subjects will receive either green tea or placebo in capsule form after their baseline measurement, which they have to consume three times daily for a period of twelve weeks.

Interventions

DIETARY_SUPPLEMENTplacebo

Subjects will receive placebo (soy oil; 757 mg/capsule, 3 capsules with each breakfast, lunch and dinner) in capsule form after their baseline measurement, which they have to consume daily for a period of twelve weeks.

DIETARY_SUPPLEMENTgreen tea (757 mg/capsule [84.5 mg EGCG + 2.1 mg caffeine ]

Subjects will receive green tea (757 mg/capsule \[84.5 mg EGCG + 2.1 mg caffeine \], 3 capsules with each breakfast, lunch and dinner)in capsule form after their baseline measurement, which they have to consume daily for a period of twelve weeks.

Sponsors

Maastricht University Medical Center
Lead SponsorOTHER

Study design

Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
BASIC_SCIENCE
Masking
DOUBLE (Subject, Investigator)

Eligibility

Sex/Gender
ALL
Age
18 Years to 50 Years
Healthy volunteers
Yes

Inclusion criteria

* BMI between 18.5-25 kg/m2 and ≥30 kg/m2 * Age between 18-50 years * Healthy * Weight stable * Dietary unrestraint * Not using a more than moderate amount of alcohol (\>10 consumptions/wk) * Not using more than 100 mg caffeine per day * Not drinking tea * Not using probiotics * Being weight stable (weight change \< 3kg during the last 6 months) * Dietary unrestraint * Not using antibiotics during the last 6 months. * Free of medication except for oral contraceptives use in women.

Exclusion criteria

* Not healthy * Smoking * Using a more than moderate amount of alcohol * Using more than 100 mg caffeine per day * Drinking tea * Using probiotics * Not being weight stable * Dietary restraint * Using medication or supplements except for oral contraceptives in women * Using antibiotics * Not meeting the criteria for BMI and age. * Pregnant or lactating women * Having allergies for the used food items will also be excluded from participation.

Design outcomes

Primary

MeasureTime frameDescription
Faeces are collected for analyzing the gut flora and fat absorptionAt three time points (baseline, 6 weeks and 12 weeks)The primary endpoint of this study is the change in gut flora; ratio firmicutes/bacteroidetes, changes in total faecal fat and change in body weight.

Secondary

MeasureTime frame
Resting energy expenditure (REE)At three time points (baseline, 6 weeks and 12 weeks)
Respiratory quotient (RQ)At three time points (baseline, 6 weeks and 12 weeks)
Three frequency eating questionnaire (TFEQ)At three time points (baseline, 6 weeks and 12 weeks)
Body composition: BMI, body fat percentage, fat mass index (FMI)At three time points (baseline, 6 weeks and 12 weeks)
Body fat distribution: waist circumference, waist-to-hip ratio (WHRAt three time points (baseline, 6 weeks and 12 weeks)

Countries

Netherlands

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Mar 2, 2026