Investigation of the effect of a green tea-caffeine mixture on weight maintenance after body weight loss in moderately obese subjects inrelation to habitual caffeine intake.
RESEARCH METHODS AND PROCEDURES:
A randomized placebo-controlled double blind parallel trial in 76 overweight and moderately obese subjects, (BMI, 27.5 +/- 2.7 kg/m2) matched for sex, age, BMI, height, body mass, and habitual caffeine intake was conducted. A very low energy diet intervention during 4 weeks was followed by 3 months of weight maintenance (WM); during the WM period, the subjects received a greentea-caffeine mixture (270 mg epigallocatechin gallate + 150 mg caffeine per day) or placebo.
Subjects lost 5.9 +/-1.8 (SD) kg (7.0 +/- 2.1%) of body weight (p < 0.001). At baseline, satiety was positively, and in women, leptin was inversely, related to subjects’ habitual caffeine consumption (p < 0.01). High caffeine consumers reduced weight, fat mass, and waist circumference more than low caffeine consumers; resting energy expenditure was reduced less and respiratory quotient was reduced more during weight loss (p < 0.01). In the low caffeine consumers, during WM, green tea still reduced body weight, waist, respiratory quotient and body fat, whereas resting energy expenditure was increased compared with a restoration of these variables with placebo (p < 0.01). In the high caffeine consumers, no effects of thegreen tea-caffeine mixture were observed during WM.
High caffeine intake was associated with weight loss through thermogenesis and fat oxidation and with suppressed leptin in women. Inhabitual low caffeine consumers, the green tea-caffeine mixture improved WM, partly through thermogenesis and fat oxidation.