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

• Faeces are collected for analyzing the gut flora and fat absorption [ Time Frame: At three time points (baseline, 6 weeks and 12 weeks) ] [ Designated as safety issue: No ]
  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.
  
  

• Resting energy expenditure (REE) [ Time Frame: At three time points (baseline, 6 weeks and 12 weeks) ] [ Designated as safety issue: No ]
  
• Respiratory quotient (RQ) [ Time Frame: At three time points (baseline, 6 weeks and 12 weeks) ] [ Designated as safety issue: No ]
  
• Three frequency eating questionnaire (TFEQ) [ Time Frame: At three time points (baseline, 6 weeks and 12 weeks) ] [ Designated as safety issue: No ]
  
• Body composition: BMI, body fat percentage, fat mass index (FMI) [ Time Frame: At three time points (baseline, 6 weeks and 12 weeks) ] [ Designated as safety issue: No ]
  
• Body fat distribution: waist circumference, waist-to-hip ratio (WHR [ Time Frame: At three time points (baseline, 6 weeks and 12 weeks) ] [ Designated as safety issue: No ]
  

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.