For example, consider this sixteenth century advice for maintenance of a good complexion, written by Hugh Platt in his book, Delights of Ladies:
“Wash the face and body of a sucking child with breast milk or cow milk or mixed with water every night and the child’s skin will wax fair and clear and resist sunburn”.
Who knew that cows produced SPF 50?

Platt goes on to show us that Elizabethan women were just as concerned with finding a deal as we are today.
"An excellent hand water or washing water very cheape:
Take a gallon of faire water, one handfull of Lavender flowers, a few Cloves and some Orace powder, and foure ounces of Benjamin: distill the water in an ordinarie leaden Still. You may distill a second water by a new infusion of water upon the seces: a little of this will sweeten a bason of faire water for your table."
This advice is odd to us, but certainly harmless. Not so the layers of mercury and white lead-filled face paint that was fashionable up until the nineteenth century. These caustic ingredients used over a long period of time could cause a lady's face to literally decompose. Charming!

By far the most dangerous beauty advice came from the soothsayers of Erzsébet Báthory, a 16th century Hungarian countess.

After beating a serving maid one evening (as one does), the countess noticed that where the blood had spattered her face there seemed to have been an enhancing effect. Her soothsayers, not wanting to become the subjects of part two of the evening's entertainment, heartily agreed. Erzsébet decided that the blood of young virgins was her ticket to eternal youth. It is estimated that over forty young women were slaughtered over the next decade to serve the countess's beauty regimen.
For my part, I'll trust Sephora to leave the white lead and virgin blood out of my next purchase.
Pictures courtesy of:
http://www.logoi.com/pastimages/elizabeth-bathory.html
http://framptonwiki541a.wikispaces.com/Group+Five?f=print
http://www.viz.nl/images/characters/kroeskoe800.jpg