An Exploratory Study on the Effects of Tea Consumption on Urinary Sodium Excretion and Blood Pressure

INTERVENTION: A Group(Tea Group):Participants will consume Deepuer tea (total theophylline content: 3 g/day), 6 bags daily. Each bag is to be steeped in 250–500 ml of water. Total daily fluid intake from tea: 1500–2000 ml, to be taken in divided doses throughout the day.;B Group(Water Group):Participants will consume purified water, 350 ml per bottle, 4‐5 bottles daily. Total daily water intake: 1500 2000 ml.; CONDITION: Hypertension PRIMARY OUTCOME: Blood Pressure; SECONDARY OUTCOME: urinary sodium excretion;urinary caffeine excretion; INCLUSION CRITERIA: 1. Stage 1 hypertension (140–159/90–99 mmHg) without antihypertensive medication use or after a 2‐week washout period. 2. Age 18–80 years. 3. Urinary sodium excretion >=130 mmol/day (spot urine). 4. No history of tea or coffee consumption within the preceding 2 weeks. 5. Provided informed consent and volunteered to participate.