There is concern in some health profession literature and the wider media that caffeinated beverages may not support normal hydration. To examine this, a systematic review was carried out to identify intervention trials that tested the impact of tea consumption on validated markers of hydration. The six trials, which mostly involved males, confirmed that tea performed in a similar way to plain water up to intakes of six servings daily. Guidelines for safe consumption of caffeine indicate that a caffeine intake of up to 400mg daily (200mg for a single serving) is safe for adults. Average tea consumption in the UK, at two to three servings daily, fits within this. Given the potential benefits of tea for heart health, dental health and cognitive function, tea consumption could rise to eight servings daily and still remain within safe caffeine limits.