Acute green tea infusion ingestion effect on energy metabolism, satiety sensation and food intake: A randomized crossover trial.

BACKGROUND: Green tea (Camellia sinensis L.) has an effect on energy metabolism, but little is known about its infusion intake impact on satiety responses. OBJECTIVE: This paper aimed at analyzing the effect of green tea on energy expenditure, satiety response, and food intake in humans. METHODS: The study involved 21 individuals (11 women, 10 men), and consisted of an open-label, crossover, randomized clinical trial (RBR-928HCW). Evaluation of subjects was performed as an acute study on two different days, after having a standardized breakfast accompanied by water or green tea. Indirect calorimetry was used to evaluate resting energy expenditure (REE), and a visual analogue scale to assess satiety. Food records were used to assess food intake along the day of the trial. RESULTS: Acute ingestion of green tea infusion with the standardized breakfast increased REE (p = 0.014) by 7.2 ± 11.7% at 240min compared to fasting (mean difference of REE between the time of 240min and fasting: +91 ± 157.6 kcal). No significant alterations were observed for substrate oxidation and respiratory quotient compared to the water treatment. A greater feeling of hunger was observed when volunteers ingested green tea (water -828.75 ± 494.2  cm min; green tea -549.8 ± 545.6  cm min; p = 0.026). No significant differences were observed regarding food intake energy and macronutrients between treatments. CONCLUSIONS: Green tea increased energy expenditure and the subjective response of hunger in healthy individuals. This study is registered in the ReBEC Platform of the Brazilian Clinical Trials Registry (RBR-928HCW).