I think what they are best for is blocking blue light that is similar to sunlight. Blocking this light allows you to get tired at a normal time instead of your brain thinking it is day time still and staying up late into the night. I've noticed that nights where I come home and read a book, or do something off of the computer I get tired at normal times and can get to sleep. If I jump on the PC and just browse the internet I can stay up until 3-5am instead of getting tired around midnight. I have read a couple studies about this but didn't want to pay $100+ to see if it is legit. Maybe for $30-40 I could try it out.