How it works: Poly hydroxy acids (PHA's) (more specifically gluconolactone and lactobionic acid) are the newest member to the hydroxy acid family. They area a new generation of alpha hydroxy acids but their bigger size gives them

a few advantages. These advantages include a slower release and more gradual penetration into the skin which allows for less irritation. PHA's main effects are through exfoliation and skin smoothing. In addition, PHAs have humectant effects that allow for increaed moisturization and increased skin barrier function. PHA's also have the benefit of having antioxidant properties.

Effectiveness: While PHAs are relatively new to skin care, there has been extensive research showing their effectiveness. Several studies have shown the benefit of PHA use on various skin types including significant improvement of fine lines, wrinkles, pore size, skin laxity, skin roughness, and mottled pigmentation. In addition, other studies have shown good tolerance when PHAs were used in conjuction with other products to help fight the signs of aging (retinoids and hydroquinone). A more recent study showed the PHAs were comparable in most areas to AHAs but where far less irritating to the skin and better tolerated in those with sensitive skin.

Where to find it: Exuviance, Neostrata

Shop for products containing the PHA's gluconolactone and lactobionic acid