I suppose the difference is I work on earth where the sun's cycle impacts on my life, whereas on a spaceship it is constantly dark outside so the body could adapt better.
I doubt any federation Star Ships are 'dark', I would think that a good percentage of the lights work in some way as sun lamps. Working in the dark (without natural sunlight) for months on-end can lead to depression and have other health implications - something that can be avoid with federation technology. The three shifts aren't actually that difference to how a lot of police forces operate.