In Give Her the Stars, Elise, the heroine, like to drink hot tea in the summer. This practice actually has benefits, provided certain conditions are met.
1) all your sweat will evaporate
2) it's not humid
If you drink a hot beverage on a hot day your stomach's thermo-sensors become overactive and send signals to the hypothalamus that you're hot, causing that organ to trigger sweating. So, if it can all evaporate, you'll lose more heat than you took in when you drank the hot drink.
If it's humid and/or you're already soggy with sweat, choose something cold.
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