No part of your body is left unaffected by a lack of sleep. Prolonged sleep deprivation can kill you. It can cause many problems to cardiovascular health, immune system, and brain functions. Lack of sleep is so dangerous that The Guinness Book of World Records has stopped recognizing attempts to break sleep deprivation records while still acknowledging other extreme activities like the highest free-fall parachute jump. Sleep deprivation can ruin your health from the inside out. However, the effects do not end with you. It can cause other problems, such as workplace negligence or driving accidents.
You may have experienced trying to keep yourself awake with difficulty. Doing so may cause microsleeps - brief moments when you enter sleep. Staying in this state is especially dangerous when driving. Being drunk causes your reaction speed to slow down. Being asleep prevents you from having any reaction at all. A few seconds of sleeping on the wheel can cause you a minor accident or worse. If you feel sleepy while driving, you can stop at the side of the road and nap. Doing this will help restore your cognitive functions. You will be able to drive more safely after that.
Lack of sleep can harm you from both the inside and the outside. Sleep deprivation is a critical issue. Everyone would be better off taking it more seriously.