Brain fog is characterized by confusion, forgetfulness, and a lack of focus and mental clarity. This can be caused by overworking, lack of sleep, stress, and spending too much time on the computer. On a cellular level, brain fog is believed to be caused by high levels inflammation and changes to hormones that determine your mood, energy and focus. The imbalanced levels of hormones make the whole system to be thrown off. Also, brain fog syndrome can lead to other conditions such as obesity, abnormal menstruation, and diabetes mellitus.