How do you determine whether a product really works?

There are tens of thousands of skin care products in the USA. So many make absolutely ridiculous claims and so many contain ingredients that can't possibly work. But how can you, the consumer, determine whether a product or ingredient is useful...or useless. It's actually nearly impossible, unless you have degrees in both chemistry and medicine. I've spent years looking at ingredients and I do believe that some work...they do what they say they do. But the vast majority of products don't work. They either contain ingredients that are too big to penetrate the skin, or they don't have enough of an active ingredient, or they have ingredients that are destroyed by sunlight....the list goes on. I spend hours reading labels of products. Sometimes I snicker and then I wonder if the clerk thinks there's something wrong with me. When I design my products, I only use ingredients with proven effectiveness. I use enough of the ingredient to make a difference, and I use the types that are biologically active. That's why my slogan is..."with my products, you don't have to read the labels...I do it for you." Have a great Thanksgiving!