We don't need to eat oils at all.
Just use coconut oil for hand lotion, it works great!
Its dehydration for sure.
Just look at how little water people drink in society and how much skin moisturisers are out there lol! Maybe society needs to eat more oil? ;)
The only time we want to use oil is for massage. If we are drinking enough water, getting enough activity and getting enough sleep, our skin will be our best ever relative to our own genetic potential.