What does a lack of sleep affect your body performance

It affects your mood and your Mental health also. It causes irritability and anger and may lessen your ability to cope with stress.

I really hope this helps ^-^

Lack of sleep can lead to many physical problems. Such as obesity, heart disease, high blood pressure and diabetes.  I've heard also, some people have actually died from lack of sleep. Sleep is needed for us to live, we aren't 100% sure why.  From what I've read in the past, there is something called cerebrospinal fluid flows rapidly through your brain to remove harmful toxins.(Nerotoxin is what builds in your brain when you sleep, and getting too much of it It can also lead to death).  Now, getting more than enough sleep is also bad for you. Many of the same reasons why. Getting too much sleep is bad, and so is not getting enough.  It can also increase chances of cancer, depression, and also weight gain. I hope this helped, and kind of gave you an explaination! I've recently been reading about this, I was really interested to see your question.