Here's some trivia, about why hot drinks were discouraged in the 18th and early 19th century. Those trying to find an evidence-based reason for things in the Word of Wisdom generally look toward modern medical advice, but to see where Joseph Smith was coming from, it helps to look at medical beliefs of his day and see how he was offering what would have sounded like typical evidence-based advice:
From a summary of observations on
influenza, from a Cyclopedia of Practical Medicine, 1833 London:
From
Observations on the Ill Health of American Women, Virginia, 1839, talking about "the diseased appearance and premature decay of our teeth":
Health and beauty
advice from 1834:
Elements of Pathology and Therapeutics, 1829:
Much earlier,
London 1765:
More health advice from
Edinburgh, 1739:
So hot drinks were behind everything from decayed teeth, to skin eruptions, to increased symptoms of influenza, inflammatory diseases and poor health in general. It's no wonder God discouraged them.