What Can Happen to You if You Don't Get Enough Sleep a Night In today's fast-paced world, it can be easy to sacrifice sleep in order to get more done. However, not getting enough sleep can have serious consequences for both your physical and mental health. In this article, we will explore what can happen to you if you don't get enough sleep a night. The average adult needs between 7-9 hours of sleep each night to function at their best. However, many people fall short of this recommendation, either through staying up late to work or socialize, or due to underlying sleep disorders. Regardless of the reason, not getting enough sleep can have a number of negative effects on your body.