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Depression is one of the most common mental disorders in the United States.
It can affect anyone at almost any age, but what causes depression in some people isnot always known.
Verywell / Joshua Seong
Potential depression causes can include genetics, brain chemistry, life events, medical conditions, and lifestyle factors.
This article discusses common causes of depression.
It covers the genetic, biological, and environmental factors that can play a role in the condition.
Factors that can contribute to depression include:
Depression does not have a single cause.
There are many factors that play a role in increasing the risk that a person will develop the condition.
Family History and Genetics
A family history of depression may increase your risk of developing the condition.
Estimates suggest that depression is approximately 40% determined by genetics.
Twin, adoption, and family studies have linked depression to genetics.
Studies show that having a parent and grandparent with depression doubles the risk of having the condition.
By better understanding how they function, gene researchers hope to be able to create more effective treatments.
It is important to remember that no single cause of depression acts in isolation.
Genetics may increase your risk and environmental influences may then determine how likely you are to develop depression.
Brain and Body Causes of Depression
Some causes of depression are related to the brain and body.
These can raise your risk for depression.
Neurotransmittersare chemical substances that help different areas of the brain communicate with each other.
When certain neurotransmitters are in short supply, it may lead to the symptoms we recognize as clinical depression.
Medications totreat depressionoften focus on altering the levels of certain chemicals in the brain.
The mind and the body are linked.
If you are experiencing a physical health problem, you may discover changes in your mental health as well.
Illness is related to depression in two ways.
The stress of having a chronic illness may trigger an episode of major depression.
Female Sex Hormones
It has been widely documented thatwomen experience major depressionabout twice as often as men.
The risk of depression declines after menopause.
Light entering the eye influences this rhythm.
People who reside in colder climates where there are short, dark days may be at the highest risk.
Poor Nutrition
A poor diet can contribute to depression in several ways.
A variety ofvitamin and mineral deficienciesare known to cause symptoms of depression.
In addition, diets high in sugar have been associated with depression.
Grief and Loss
The symptoms of grief are expected to subside over time.
But when symptoms get worse, grief may turn into depression.
National Institute of Mental Health.Major depression.
2018;9:1047. doi:10.3389/fphys.2018.01047
Zisook S, Shear K.Grief and bereavement: What psychiatrists need to know.World Psychiatry.
