What's it used in? Skincreams, toners, shampoos and masks.

What does it do? It's claimed that it can nourish ageing skin.

Any controversy? Derived from the placenta, an organ that develops in female mammals to help provide nourishment and oxygen to the fetus. But it produces hormones which can affect those of the consumer. A 1998 study found it can lead to premature sexual development in children. Also of concern is that the source is often from aborted fetuses or slaughtered animals and may not be hygienic.