Different types of books are going to work for different people - what makes me an insomniac may turn you into a narcoleptic - but I think a primary aim of an author should be to interest the reader to the point that they forget their circumstances, whatever that may be.
The most basic method is to pose a 'Will they, won't they' question - will they, won't they discover the truth/get together/find out who dunnit. Part of the skill is for the answer to appear obvious, so the reader thinks they know what they're getting, and then to do something entirely plausible but completely unexpected. That'll keep them reading.
A mistake many new writers make is to believe that the action has to be big and dramatic to make it unputdownable. I read Family Album by Penelope Lively a couple of months ago and was riveted, even though it's a very small story on a limited domestic scale. The characters were real and consistent, but never predictable. What was going to happen next? Where was it going to end? I never knew and that kept me reading late into the night.
So if you want to keep your readers from going to zzzz then keep them guessing the answers to your story questions, and then give them answers they weren't expecting.