It's definitely better to sleep on a schedule which is closer to a natural rhythm (sleep at night and wake up when the sun is out). I know there are many people who don't because of work and other factors. I'm not sure what problems they may face because of it. Insomnia is another yeast and/or heavy metals symptom, so it's possible that your not sleeping at night is related to that.
I used to be a night owl until I got an early morning job. Then my rhythm switched and now I always wake up between 7 and 8 AM. I had some trouble waking up (feeling tired, needing caffeine, zombie-like feeling) until I began the anti-yeast diet. Now I wake up just fine even though I don't drink caffeine.