Green tea with high-density catechins improves liver function and fat infiltration in non-alcoholic fatty liver disease (NAFLD) patients: A double-blind placebo-controlled study

• Published in: International journal of molecular medicine 2013-11, Vol.32 (5), p.989-994
• Main Authors: SAKATA, RYUICHIRO, NAKAMURA, TORU, TORIMURA, TAKUJI, UENO, TAKATO, SATA, MICHIO
• Format: Article
• Language: English
• Subjects: Abdomen; Alcohol; Binding sites; Biochemistry; Biopsy; Body fat; Body mass index; Double-blind studies; Eating behavior; fatty liver; flavonoid; Flavonoids; Hepatitis; Inflammation; Iron; Liver diseases; metabolic syndrome; non-alcoholic fatty liver disease; non-alcoholic steatohepatitis; Oxidative stress; Patients; Spleen; Tea; Ultrasonic imaging; Urine
• ISSN: 1107-3756; 1791-244X
• DOI: 10.3892/ijmm.2013.1503

Catechins, a major component of green tea extract, have anti-hyperlipidemic effects. The present study investigated the effects of consumption of green tea with high-density catechins in non-alcoholic fatty liver disease (NAFLD) patients. Seventeen patients with NAFLD consumed green tea with high-density catechins, low-density catechins or a placebo for 12 weeks in a randomized double-blind study. Ultrasonography and computed tomography (CT) were performed at baseline and after 12 weeks. Serum alanine aminotransferase (ALT) levels and urine 8-isoprostane were monitored and compared to baseline at 4, 8 and 12 weeks. Body fat was significantly decreased in the high-density catechin group compared with the placebo and low-density catechin groups after 12 weeks of consumption. All the patients in the high-density catechin group showed a significantly improved liver-to-spleen CT attenuation ratio compared with the placebo and low-density catechin groups after 12 weeks of consumption. The high-density catechin group significantly decreased serum ALT levels and reduced urinary 8-isoprostane excretion compared with the placebo and low-density catechin group after 12 weeks of consumption. Based on a reduced proportion of body fat as estimated by bioimpedance measurement, increased liver-to-spleen CT attenuation ratio, decreased serum ALT levels and reduced urinary 8-isoprostane excretion, we concluded that 12 weeks of 700 ml per day of green tea containing >1 g catechin improved liver fat content and inflammation by reducing oxidative stress in patients with NAFLD.