How much of an impact does a lack of sleep have?

8-9 hours is normally enough and quite healthy I hear.

There is, in fact, a wide range of sleep time that is considered "normal." While the average normal amount of sleep is around 7.5 hours per night, there are some people who do just fine on 5 hours per night, and some who require as much as 9 hours per night. The key is to find the right amount for you. The best way to tell is by seeing how you function during the day.

For example, if after 6 hours of sleep you feel refreshed in the morning and awake during your daylight hours, then you don't need more than that. If, on the other hand, you need 9 hours a night to feel refreshed and to function well during the day, then that is what your individual requirement is and sleeping the "normal" amount of 7.5 hours per night will actually leave you sleep deprived.

If you are getting what you consider to be an adequate amount of sleep and are still unrefeshed and sleepy, then you might have an organic sleep disorder and should consider seeking professional consultation.

8-9 hours is normally enough and quite healthy I hear.

You're going to bed too late. *puts maternal hat on* If you've just done your GCSE's and are only 16, then you need more sleep. Get your exam results, try and get back into a normal bedtime routine and if you're still feeling stressed out, see the GP for more advice.
And yeah - a lack of sleep and stress can mess up pretty much everything about you. Good luck for tomorrow!

6-7 hours is normal. Every hour after that shortens your life...

nooo.. that is way too much sleep aparently. According to statistics anyway. 6-7 hours is normal. Every hour after that shortens your life...

That's a good point, actually. Although for some reason I think the time when you go to bed can slightly affect the quality perhaps? That might more be the problem.

You could be right, I know this is going to sound outrageous, but try to goto bed at 10-10:30 and wake up at 7, go for a run for abut 10mins and see how you feel. Certainly did help me with my personal problems.

Don't worry- sounds fairly rational to me! I enjoy running, but I tend to go in the evenings as opposed to the mornings. Did you feel better for it?

I'm not too bad any more, but I used to have really bad insomnia. Some nights I could only sleep for about 1-2 hours (and it was broken, due to nightmares/dodgy thought processes/etc). Though for me it was a symptom of a pre-existing illness.

I could barely function at the time. My concentration was low, my energy levels were low, I was never motivated to do anything. It often took me several times as long to complete simple tasks as I had to keep taking breaks to either allow my energy levels to recover or to remember what it was I was supposed to be doing.

I would definitely say getting the sleep you need to be able to function properly the next day is important.

Yep, also the running helped sort out problems/issues and get some proper fresh air, especially in the winter!