Tea decoctions prevent body weight gain in rats fed high-fat diet; black tea being more efficient than green tea

In contrast to the usual tea infusion, the anti-obesity effect of tea decoction (TD) is poorly documented. Here, we compared and contrasted the chronic effect of short-time decoction (15-min) of green versus black tea (GTD, BTD) prepared at a dose of 5% on lipid digestion and weight gain in rats fed high-fat diet (HFD) for 10 weeks. The rats were assigned into three groups (n = 10–12 each) and given ad libitum the HFD + water (CTRL) or GTD (GTGr) or BTD (BTGr). The food and fluid intake were measured daily and weight gains once/week. The fecal matters were collected twice/week for TPC, caffeine, total lipids and triglycerides (TG) analysis. In addition, the liver, perirenal and epididymal adipose tissues (AT) were removed and blood was collected for the same analysis and leptine level. 10-weeks TD consumption increased fecal TG excretion (+170 in GTGr and +230% in BTGr; P < 0.001 vs CTRL). It reduced liver TG by 25 and 35% (P < 0.001 vs CTRL) and plasma TG by 36.6 and 48% (P < 0.01 vs CTRL) in GTGr and BTGr, respectively. The AT gains were reduced by 26.5 and 56.4% in GTGr and 60% in BTGr (P < 0.001 vs CTRL). The reduced AT was consistent with a reduction of 27 and 59% of leptin levels (P < 0.001 vs CTRL) and 21 and 55% of weight gains in GTGr and BTGr (P < 0.01 vs CTRL), respectively. Chronic GTD and BTD prevent fat storage in the liver, lowering blood lipids and glucose, increasing fecal excretion of TG, decreasing AT and weight gains in rats fed HFD, with a strong effect of BTD compared to GTD. Therefore, these beverages containing high amounts of TPC and caffeine could constitute a natural alternative in the prevention of obesity.