So we’ve talked about how super-hot showers can dry out your skin, and the same principle applies here. Just like exposing the skin elsewhere on the body to scalding hot water can weaken the barrier by disrupting your natural lipids, the same can be true for the lips when you're drinking piping hot coffee.
You’re probably thinking: OK, iced coffee it is! But that’s not the whole story. See, coffee is actually a diuretic—so it can be dehydrating when drunk in excess. In fact, gastroenterologist Will Bulsiewicz, M.D., MSCI, says he always checks the lip area for signs of dehydration: "Pay attention to your lips. If I notice my lips starting to get dry, that tells me I'm pushing the coffee more than I should," says on the mindbodygreen podcast.
Although, you should know that moderate coffee drinking won't have a huge effect. (Don't worry, no need to curb your habit entirely.) So you can still enjoy a cup or so of hot coffee, if you please, and be just fine—but if your lips start to feel tight or chapped and you aren’t sure why, you might want to keep your hot beverage intake in mind. That goes for hot drinks other than coffee, too—if you consistently sip on warm lemon water, tea, or matcha throughout the day, it may be easier to dry out the sensitive lip area.