Sorry if this has been covered somewhere else on the blog, but I've read in a number of places that not only Retin A, but also peptides are beneficial to the skin by boosting collagen production. First, I guess I'm not sure what 'boosting collagen production' actually does for the skin. And - if peptides do benefit the skin beyond just moisturization, have they been studied - is there any evidence that they benefit skin, e.g., improve lines/wrinkes?
Are certain peptides more likely to work than others? How do they work (if they, in fact) do work? What drugstore products contain peptides?