This definitely has a negative effect. Probably bigger than you imagine.

Source: I'm ending my Bachelor's degree (I've been 4 yrs in the battlefield) and this semester I had weekly homework. I needed some heavy concentration skills. Besides I usually had less time than needed for finishing those, and teachers aren't likely to give extra time, so I didn't sleep the whole night about once a week. Then, during the day seeing from my desk happy people everywhere sharing spontaneous words, emotions and screaming, while I was like a ghost in the shell, numb, zombie-like 24/7. Besides this faculty fosters an moderate spencerian-like competitive attitude, "law-of-the-jungle" like. i think it's the result of being in a math/science oriented campus where negative emotions are rationalized and when showed, seen like a lack of responsibility from the individual he/she should treat. I ended being quite more cynical than I needed because of this, luckily it's not full like that and it's pretty likely there are some laid-back people for just relaxing instead of showing an inferiority complex via competence/distrust. I ended distracted to the point I slept more no matter what I had to do. World wasn't a Heidi's prairie after it but it improved. Definitely. Same happy happy joy joys around, same kind of homework and difficulty, but I was in better condition to forget my context and focus on what I needed. Things resulted to be simpler than what I expected more than once.

Another things that may help:
- Sports. Really. Just twice a week it's a reasonable booster. No matter of your condition unless you actually have a disease/disability or doctor says just don't.
- Lazy times: In my place they think the best one is the one who keeps all the time breaking his mind for success and excellence. I think that's truly more a fantasy archetype rather than a realistic model to follow. If you notice you aren't productive, don't push yourself. That won't work; besides not achieving the task, you'll only lose time and feel negative. Try enjoying moments where you absolutely stop thinking on any duty/homewhork/test/whatever.