This randomized, double-blind, crossover trial was conducted in 12 healthy men who underwent 7-days unhealthy lifestyle (UL) including physical inactivity (-50% steps/day) and overfeeding (+50% kcal/day). Meanwhile, subjects consumed green tea (3 doses/day) or placebo.

As a result, increased postprandial glucose and insulin have been measured in the placebo group, while green tea decreased postprandial glucose and insulin (both p < 0.05). Decreases in carotid artery reactivity and femoral flow-mediated dilation were observed in the control group, while green tea prevented these effects (p < 0.04 and p < 0.001, respectively).

Authors concluded that 7 days of physical inactivity and overfeeding impair insulin homeostasis and vascular function. These effects were mitigated by a daily intake of catechin-rich green tea.

Roberts KA, Draijer R, Hopkins ND, de Graaf Y, Holder SM, Carter SE, Thijssen DHJ, Low DA. Impact of green tea on the deleterious cardiometabolic effects of 7-days unhealthy lifestyle in young healthy males. Physiol Rep. 2021 Mar;9(5):e14720. doi: 10.14814/phy2.14720. PMID: 33682367.