Do tea and coffee dehydrate you?

Asked by: Lizzie Wray, Bournemouth

Health experts often warn of the need to keep hydrated, but some insist tea and coffee don’t increase hydration levels. That’s supposedly because they contain caffeine, which makes us urinate more. But while caffeine can have a diuretic effect, a 2016 study by a team from various UK universities showed the amounts in tea and coffee had negligible impact.

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