The connection between long life and personal hygiene was an important par of Hipocratic medicine and was later popularized by scores of works on proper living, most notably those of Luigi Cornaro and George Cheyne. Cornaro’s Trattato de la vita sobria, first published in 1558, and George Cheyne’s Essay of Health and Long life, published in London in 1724, as well as other moral treatises and regimen texts, emphasized the six Galenic “non –naturals”: air, food and drink, sleeping and waking, exercise and rest, the evacuations, and the passions of the mind. Abuse of one or more of the non – naturals could result in disease; thus moderation was the key to a healthy life.
Reference: Proceedings, American Philosophical Society (vol. 139, No. 2, 1995)