Effects of green tea and its epigallocatechin (EGCG) content on body weight and fat mass in humans: a systematic review

The prevalence and incidence of overweight and obesity worldwide continues to increase, as well as diseases related to these conditions. This is attributed to an increase in energy intake and a decrease in energy expenditure. Consumption of green tea has been linked to a reduction in body fat and body weight. However, research on green tea has been very diverse. This review assesses the investigations that have been made with green tea and its epigallocatechin gallato (EGCG) content, evaluating its effect on body fat and body weight in humans. A search was made in the PubMed and Web of the Science databases that gave a first total result of 424 potential articles; 409 were excluded and 15 articles were used for this systematic review. Research has been very varied, however, daily consumption of green tea with doses of EGCG between 100 and 460 mg/day has shown greater effectiveness on body fat and body weight reduction in intervention periods of 12 weeks or more. In addition, the use of caffeine doses between 80 and 300 mg/day has been shown to be an important factor for this effects, when the participants did not have a high caffeine intake (> 300 mg/day) prior to the intervention.