As with most conditions that affect mental health, the exact cause of generalised anxiety disorder (GAD) is not fully understood.
Some people develop the condition for no apparent reason. Others may develop GAD after a major stressful incident.
Neurotransmitters and anxiety
Research has suggested that GAD may be caused by an imbalance of certain chemicals that occur naturally in the brain. These chemicals are known as neurotransmitters.
Two neurotransmitters thought to affect anxiety are serotonin and noradrenaline. If the level of these chemicals in your brain becomes unbalanced, it can significantly affect your mood and increase your likelihood of developing anxiety-related conditions such as GAD.
However, GAD is most likely to have a complex combination of causes, rather than being triggered by just an imbalance of brain chemicals.
Combination of causes of anxiety
Researchers believe that GAD is caused by a combination of factors, including:
- your body's biological processes
- genetics (the genes you inherit from your parents)
- your environment
- your life experience
