I've found I don't have the problem with my Kindle that I do on the computer. My hands are so arthritic that I tend to have all of my larger books in Kindle format - and much of my fiction (I borrow Kindle books from my library as well as purchase them). I still use actual books and the format depends on the topic (graphics and tables are always actual books) OR size. Some of my most beloved books are huge...so Kindle for them!

Again, I'm quite sensitive to screen time before bed but my Kindle Paperwhite doesn't bother me and it does have adjustable lighting.