Bakuchiol is a plant-derived antioxidant (it's vegan!). It is often called the replacement for retinol although it is not part of the same family.

It has similar effects as retinol: skin smoothing, reducing discoloration, and preventing wrinkles. It does not cause as much irritation as traditional retinoids.

Propanediol is an all-star ingredient. It softens, hydrates, and smooths the skin. 

It’s often used to:

Water. It's the most common cosmetic ingredient of all. You'll usually see it at the top of ingredient lists, meaning that it makes up the largest part of the product.

So why is it so popular? Water most often acts as a solvent - this means that it helps dissolve other ingredients into the formulation.