Asked by: Rhiannon Harris, by email
During rest, your body generates around 360 kilojoules an hour, so a cup of tea is equivalent to about five minutes of heat production. The heat goes straight to your core, and can cause your body to think you're hotter than you really are. You'll sweat more and divert hot blood to your skin, which might cause you to lose more heat than you actually gained from the drink.
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