Emulsifiers such as linoelic acid are used to ensure a smooth mixture and consistency. Silicone is often incorporated to give a pleasing textural feel, and makes application easier. Sunscreens are also added and may include octyl methoxycinnamate, titanium dioxide or zinc oxide. With most things in life, you only get what you pay for. Cheap skin-care products will have cheap ingredients.
Ingredients go in and out of fashion.
The cosmetic companies seem only to be interested in the latest, most saleable ingredient. Enormous resources are used to develop ingredients that are making skin products more effective than ever. In addition, the cosmetic companies are always seeking to discover new, more effective ways of getting ingredients into the skin. Liposomes are commonly used. They are tiny hollow spheres filled with active ingredients, which are absorbed into the skin and release their contents precisely where they are most needed - under the surface into the deeper layers of the skin.