3. Sleep Deprivation
The most common cause of dark circles under the eyes is fatigue. Not getting enough sleep leads to your skin becoming increasingly pale. This leads to blood underneath the skin becoming more visible.
When this happens, the area underneath your eyes appeared darker and bluer. In addition to a lack of sleep, being mentally exhausted will also lead to dark circles. To avoid dark circles due to fatigue, be sure to get enough rest and give yourself a break every once in a while. If you find yourself chronically exhausted, see your doctor for help. Even if you get eight hours of sleep every night, you may still end up with dark circles under your eyes.