Cleopatra was onto something when she used milk to bathe in. As expensive as this treatment was in ancient Egypt, Cleopatra recognized that the milk did something for her skin. French and English aristocracy also indulged in milk baths in the sixteenth and seventeenth centuries.

Now we know exactly what milk did for their skin to make it such a celebrated beauty treatment. The natural lactic acid found in milk is a form of alpha-hydroxyl-acid (an ingredient which can be found in some of the most expensive exfoliating products in the world). This type of acid gently dissolves proteins to exfoliate dead skin cells, which reveal fresh, younger looking skin underneath.

The lactic acid found in milk is extremely mild, so don’t worry, it won’t strip or irritate the skin like 10% concentration of pure alpha-hydroxyl-acid can. In fact, milk is quite soothing on dry skin. Even though it has lactic acid in it, milk has been used to soothe irritated skin.

Another benefit of bathing in milk is the fat content. Since the milk is not being digested, the higher the fat content, the better (!), especially for dry skin.