If you or someone you know is suffering from depression, it’s normal to want to know where it comes from and what causes it. The truth is that depression is a complex medical condition that is still not completely understood. The good news is that medical professionals know enough about it to be able to help alleviate symptoms in people who are going through depression. Rather than a single factor, a combination of biochemical, psychological, genetic, and environmental factors is believed to cause depression.
Depression is considered a type of mood disorder in which the neurotransmitters — chemical messengers that help the brain and other parts of the body communicate — appear to be out of balance. These chemicals, including serotonin, norepinephrine, and dopamine, help regulate many physiological functions. Experts believe that lower levels of these neurotransmitters may play a role in why some people are more susceptible to depression.
Depression can occur in people with no family history of the disease. However, there does appear to be some genetic link to depression. Having an immediate family member with depression can increase your risk. Studies of identical twins who were raised in separate homes showed that when one twin was diagnosed with depression, the other twin developed the same disorder 67 percent of the time
The brain is highly malleable and constantly changing in response to its experiences. That’s in part why scientists believe depression is a product of both our genes and our environment. Traumatic life events, such as the loss of a loved one, distressing financial situations, or big changes like a move can all potentially trigger symptoms of depression.