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Pergunta: O que é que aqueles nos dias de Joseph Smith saber sobre suor e poros?
Question: What did those in Joseph Smith's day know about sweat and pores?
Those in Joseph Smith's day did not know much more about sweat and pores than classical writers of 2500 years earlier did.
American medicine at the time of Joseph Smith was still exceedingly primitive. Medical practitioners still drew heavily on the theories and works of antiquity for medical theory, diagnosis, and treatment.
As discussed above, the concept of "pores" in the skin for sweat and other substances is an ancient one in western medicine. Despite this, the pores had never been definitively demonstrated throughout the skin.
A popular medical textbook of the time, Buchan's Domestic Medicine Modernized, etc. (1807) blamed the following diseases on blocked perspiration: most fevers, gout, rheumatism, scurvy, asthma, epilepsy, hypochondria, and inflammation of lung, kidney, bowel, and brain. 
Thus, contrary to the critics' claims, Joseph Smith or his contemporaries were no better suited to know the facts about skin pores or sweat than classical writers of 2500 years earlier. Theory and knowledge on the subject had not advanced much, and a rural farmboy such as Joseph would hardly have been aware of any of the learned discussions taking place on the topic, which were not terribly advanced anyway.
Sweat glands and associated structures were finally demonstrated to exist in 1835, six years after the translation of the Book of Mormon.  The modern understanding of sweat and the role of the skin in fluid homeostasis was fixed around the turn of the century. 
Joseph Smith had as much chance at being right about the relationship between sweat and pores as an ancient author writing thousands of years earlier.
- Renbourn, 147–148.
- Renbourn, 149.
- Renbourn, 150.