Let's talk about the ingredients in cosmetics | The Right Chemistry 

Collagen applied on the skin won't penetrate, it's only going to give you an temporary and superficial effect. Collagen taken orally is broken down by the intestines, and no effect on the skin have been seriously proven yet.

no its too large a molecule to go through the skin. Retinol is the only proven ing that does this.

@@EverythingLvl Thank you for answering my question.