Vitamin A is present in its ester form, which is a combination of retinol and palmitic acid, and which constitutes the group of compounds known as retinoids. This family of compounds is recognized as a highly effective skincare ingredient, with tretinoin being the most notable of them, given that it has been approved by the FDA for anti-aging purposes. Retinol is also a major component of this family, although it is a few steps away from tretinoin in terms of metabolism. To put it simply, tretinoin, or retinoic acid, is the form of the ingredient that our skin cells can recognize, and retinyl palmitate has to be converted by our body’s metabolic system in order to work.