Causes of insomnia can be cataloged into two categories: genuine health issues and the modern world syndrome. Health causes of insomnia include depression, anxiety and illness. Whether a mental illness or a physical illness, these causes of insomnia have to be treated individually and simultaneously with the insomnia itself. Although linked with ideas of not being able to fall asleep, insomnia actually has four types of symptoms. The first is sleeplessness and others include frequent awakenings in the night, restless leg syndrome and waking too early in the morning.

Physicians try to convince patients to practice good sleep hygiene as a way of reducing causes of insomnia. These practices are often best applied to those suffering from modern world syndrome. During times of tragedy and high stress such as world altering events like hurricanes, terrorist attacks or a death of a loved one, insomnia may very well occur. High levels of stress can trigger fight or flight in the body's nervous system. This very primal reaction is a biological defense mechanism that kept people alive when, for example, a saber tooth tiger attacked them.

In the modern world, this same defense mechanism is actually a contributor to stress. Fight or flight floods the body with hormones, suppresses digestion, purges wastes and kicks up adrenalin so people can run further, fight harder and have the best opportunity to survive. The problem in the modern world is that there are no dragons or tigers to slay. Yet the build up of this response everyday is one of the causes of insomnia in a number of people. 

While the occasional sleepless night is to be expected (just ask any parent) and over the counter sleep aids can help, a persistent problem can actually continue to contribute to the causes of insomnia. When the circadian rhythm is broken, it needs to be repaired before the body begins to collapse from an inability to perform its own functions. So if stress causes of insomnia are keeping people awake, it's time to make some healthier choices for both the sake of their health and their sleeping problems.