The Natural History of the Tea-Tree With Observations on the Medical Qualities of Tea, and Effects of Tea-Drinking was published in 1772 by John Coakley Lettsom (1744–1815), a physician and philanthropist, whose first action on inheriting his family plantation in 1767 was to free all its slaves. Lettsom founded the Medical Society of London in 1773.
The book began with a description of the tea plant and its cultivation and harvesting in China, as well as the preparation of the leaves for use locally and abroad. Dr. Lettsom then turned to the medical uses of tea, lamenting that so little scientific evidence exists for either its beneficent or its malign properties.
After performing various experiments and considering the physical and social consequences of tea-drinking, the doctor concluded that tea should be avoided, because its enervating effects lead to weakness and effeminacy, advice which mostly fell on deaf ears.