What Causes Depression?
Medically reviewed by Aleesha Grier, PsyD
There is no single cause of depression. Instead, there are several potential risk factors for depression, with genetics and biological, environmental, and psychological factors all contributing. Depression can occur alongside other mental or physical illnesses, following traumatic life events, or independently. Sometimes, the cause is unknown.
This article discusses the most common causes of depression, explores some of the less common ones, and explains when it's time to see a healthcare provider for treatment.
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What Causes Depression: Current Understandings
While there is no clear, singular cause of depression, certain factors have been linked to the condition. For example, people who experience childhood trauma or abuse are more likely to develop depression. Also, people with one or more blood relatives who experience depression are more at risk.
Abuse or Trauma
Abuse and trauma are significant risk factors for depression. This includes hardships experienced as children that lead to depression in adulthood. Emotional abuse during childhood is most likely to cause depression in adulthood, followed by neglect, sexual abuse, domestic violence, and physical abuse.
This connection between abuse, trauma, and depression is not limited to childhood. Depression can happen as a result of abuse or trauma, regardless of age.
Genetic Predisposition
While depression can run in families—having a blood relative with depression increases your risk—scientists have not linked any specific gene to depression.
One systematic review found that in more than 60% of major depressive disorder cases, genetics was not the primary cause. The researchers in this review believed this percentage to be even lower for depression not diagnosed as a major depressive disorder.
Mental Health Disorders
Higher rates of depression are linked to other mental health conditions. For example, depression and anxiety often co-occur. Research shows that over 70% of people with depression also have anxiety symptoms. This does not mean that one causes the other; instead, people who face one are more likely to experience the other.
Chemical Imbalance: An Incomplete Explanation
Depression is linked to chemical imbalances in the brain. However, a correlation between chemical imbalances in the brain and depression does not imply causality. Meaning that just because they are related does not mean that chemical imbalances directly cause depression.
Our thoughts can change the chemical balance of our brains. For example, gratitude practices promote serotonin and dopamine—chemical messengers that promote positive emotions. These brain chemicals help you process your feelings and prevent depression symptoms. People with depression have lower serotonin and dopamine levels.
Adverse life experiences can also impact our thought patterns and contribute to depression. So, yes, chemical imbalances can play a role in depression, but it's important to consider other contributing factors, too.
What Causes Severe Depression Symptoms?
Researchers are still working to understand why some people experience more severe depression symptoms than others since the underlying causes are the same. Severe depression can lead to thoughts and attempts of suicide.
Risk factors of severe depression symptoms are categorized into four different areas:
Personal risk factors such as chronic illness, substance misuse, and financial challenges
Relationship risk factors such as a lack of social support, bullying, and challenges with friends or family
Community risk factors such as limited access to healthcare services and high crime rates
Societal risk factors such as mental health support and treatment stigmas and unsupportive media exposure
Severe depression symptoms include:
Changes in appetite
Weight changes
Sleep and energy level changes
Disinterest in activities
Feeling sad, hopeless, worthless, guilty, or empty
A subtype of depression called treatment-resistant depression happens to about 30% of people with depression. It occurs when depression symptoms remain after trying various treatments.
If you experience treatment-resistant depression, continue working with a healthcare provider to find an effective treatment plan. Sometimes, it can include multiple approaches, such as taking medications long enough for them to build up to an effective dose, education, lifestyle changes, and psychotherapy.
Secondary Causes of Depression
Depression affects about 5% of adults—4% of men and 6% of women. There are often multiple causes that can result in depression.
For example, a woman who experienced trauma during childhood is more likely to experience postpartum depression. In this case, the depression causes are trauma, pregnancy, and childbirth.
Here are some other examples of secondary causes of depression.
Life Events Linked to Depression
Life events and changes can increase your risk of depression—even positive ones—such as marriage or a new baby. This is because positive events can involve stressful adjustments.
Research shows that people who experience life events associated with higher levels of stress are more likely to have depression symptoms. Some examples of stressful life events include:
Retirement
Graduation
Marriage/divorce
Giving birth/adopting a child
Death of a family member or friend
An injury
Chronic Disease
Living with a chronic (long-term) disease increases the risk of depression. More than 10% of people with cancer experience depression. Up to half of those with autoimmune diseases experience depression symptoms. Individuals struggling with chronic pain, thyroid disease, diabetes, and heart disease are also more likely to suffer from depression.
Coping with physical symptoms that affect your daily life for months or years can be physically and mentally challenging. However, there are many things people with chronic diseases can do to improve their quality of life and decrease the risk of depression.
Location or Life Situation
Your geographic location can impact your risk for depression. For example, people who live in the Appalachian and southern Mississippi Valley areas experience the highest rates of depression in the United States.
These depression rates may be related to lower income levels, higher rates of disease, and less access to healthcare resources. Other life situations that can also contribute to depression include unemployment, underemployment, feeling unfulfilled, experiencing discrimination, and not feeling supported and understood by others.
Feeling Depressed Without a Clear Cause
There isn't always a clear cause for depression. Hormonal changes—such as those that happen to women during puberty, perimenopause, and menopause—can contribute to depression but are not as apparent as other causes.
Seasonal changes—usually those occurring in the late fall and winter—can lead to a type of depression called "seasonal affective disorder."
Certain nutrient deficiencies, such as too little omega-3 fatty acid, vitamin B or D, magnesium, iron, or zinc, can also impact depression. Even when the cause is unknown, a healthcare provider can still treat your depression.
Depression Causes in Children and Teens
The causes of depression among children and teens are similar to those in adults. Depression may result from a combination of factors, such as challenges at school, bullying, and family or home life difficulties.
Social media is a significant risk factor for depression, with the chances of experiencing mental health challenges such as anxiety or depression being twice as high among children and teens who use social media for three or more hours per day.
Parents and other adults should communicate with children and teens about mental health in a supportive way.
Speaking to a Provider About Your Depression
If you or someone you know is experiencing symptoms of depression or another mental health condition, help is available. If you have a primary care provider, ask them for a referral. They can help you find a mental health provider, such as a psychologist, psychiatrist, therapist, or counselor. You can also find a therapist online.
When seeking help, it is essential to be honest with your provider and share your thoughts, feelings, concerns, and relevant life events openly.
Summary
There are various causes for depression, and sometimes, the cause is unknown. Some factors that increase your risk for depression include abuse or trauma, chronic health conditions, having a genetic predisposition, and stressful life events. It is important to seek the support of a qualified healthcare provider to discuss your depression symptoms and learn about treatment options.
Read the original article on Verywell Health.
