Objective: The purpose of this study was to evaluate the effects of a catechin-rich beverage on body fat and cardiovascular disease risk factors in obese children and to verify the safety of its use.
Methods and procedures: Obese or near-obese Japanese children were recruited for this study. A double-blind, randomized, controlled study was performed with a 4-week lead-in, a 24-week beverage ingestion period and a 12-week follow-up. Subjects ingested green tea containing 576 mg catechins (catechin group) or 75 mg catechins (control group) once per day for 24 weeks. Randomization was stratified by gender, age, and BMI. Subjects were instructed to maintain their usual lifestyles during the study period.
Results: Data were analyzed using samples from 40 subjects (catechin group; n = 21, control group; n = 19). There were no significant differences in major outcome variables, such as body fat mass, between the catechin and the control groups. When, however, the analysis was stratified using the median of the week-0 values, the decrease at week 24 in waist circumference, systolic blood pressure, and low-density lipoprotein cholesterol in the catechin group was significantly greater than that in the control group for the above-median category. Ingestion of the catechin-rich beverage was not associated with any adverse effects.
Discussion: These findings suggest that ingestion of a catechin-rich beverage ameliorates serious obesity and cardiovascular disease risk factors without raising any safety concerns in Japanese children.