While a messy bed could end up benefitting your health, a messy bedroom will not. Messy bedrooms have been found to reduce sleep and increase drowsiness during the daytime. Having a cluttered bedroom will also tend to increase stress, anxiety, and can even aggravate mental illnesses. If you walk into your room and see a clean and tidy space, you are going to be able to relax and fall asleep easier. If you walk into what looks like a battle zone you will feel stressed and have trouble falling and staying asleep. So, if you want to really improve your sleep habits, make sure that your sleeping environment is as pristine as it can be.