A Randomized, Placebo-Controlled Study on the Safety and Efficacy of Daily Ingestion of Green Tea ( Camellia sinensis L.) cv. "Yabukita" and "Sunrouge" on Eyestrain and Blood Pressure in Healthy Adults.

The green tea ( Camellia sinensis L.) cultivar &ldquo;Sunrouge&rdquo; contains anthocyanins, catechins and flavonols. To determine whether ingesting green tea containing anthocyanins improves visual function and blood pressure (BP) in healthy adults, a randomized, double-blind, placebo-controlled study was performed. A total of 120 healthy subjects, aged between 20 and 60 years and with a systolic BP (SBP) value of &le;125 and <155 and a diastolic BP (DBP) value <95, or a DBP of &le;75 mmHg and <95 mmHg and a SBP <155 mmHg, were randomly assigned to one of three groups. For 12 weeks, the placebo group received barley extract without catechin; another group received &ldquo;Sunrouge&rdquo; extract containing 11.2 mg anthocyanin and 323.6 mg epigallocatechin-3- O -gallate (EGCG); and a third group received &ldquo;Yabukita&rdquo; extract containing 322.2 mg EGCG. Home BP, accommodation ability, visual analog scale questionnaires for eyestrain, and metabolic-associated markers were analyzed at weeks 0, 4, 8, and 12 of the intake period. The ingestion of &ldquo;Sunrouge&rdquo; tea significantly improved accommodation ability and eyestrain in subjects younger than 45 years and in subjects who operated visual display terminals every day. It also elevated BP. &ldquo;Yabukita&rdquo; tea ingestion significantly increased serum adiponectin levels. No adverse effects were observed. We conclude that long-term intake of &ldquo;Sunrouge&rdquo; tea containing anthocyanins and flavonols might improve visual function.