Clinical depression is a very common illness so what causes depression? According to the National Institutes of Mental Health (NIMH), around 16.2 million American adults will suffer from major depression in any given year.
That’s 6.7% of the U.S. population. And statistics published by MIT show that at least 17% of Americans will experience a major depressive episode at some point in their lives.
Why do these statistics exist? What actually causes depression? It’s a complex illness; many factors contribute to it or make it worse.
The way depression shows itself is different for different people and often has to do with your past and your environment.
Researchers have been searching for the causes of depression for years, and they’ve developed many theories. Here are four of the main ones.
1. Genetics
One of the most influential factors in the onset of major depression is outside your control: your genetic code. Stanford Medicine suggests that in most cases of depression, around 50% of the cause is genes.
Two people, with two different sets of genes, could experience the same traumatic life event, yet one develops depression while the other doesn’t. Different types of depression (like bipolar disorder, psychotic depression, and dysthymia) may involve different genes.
Research suggests that if you have a parent or sibling who’s suffering from depression, you are up to three times as likely to have the condition. Still, it’s difficult to say how much of this is due to genetic factors and how much relates to your environment.
Both are causes of depression, but their exact influence and relationship to each other are still being studied. It seems likely that your environment and your genes interact in a way that determines your risk of developing depression.
2. Substance Abuse
Substance abuse (alcohol or drugs) often go hand-in-hand with major depression. This is known as comorbidity or having two mental health conditions at the same time.
A large body of data shows a strong link between alcohol or drug abuse and major depression. While 17% of Americans overall will experience depression, 30% of substance abusers and alcoholics have depression. Researchers say that around 27% of depressed people also struggle with substance abuse.
How does substance abuse cause depression? It can happen in a variety of ways.
For example, you may be dealing with a lot of emotional pain and stress and use alcohol and drugs to self-medicate. Regularly drinking or using drugs makes you feel euphoric and provides temporary relief. But when you sober up, you experience a “crash.” This may come along with:
- Anxiety
- Increased bouts of low mood
- Irritability
Drugs and alcohol still provide relief, so you continue to use them. To avoid the lows when you come down, you increase how much of the drug you use and how often you use it.
A downward spiral sets in. Withdrawal depression turns into clinical depression if it lasts for two weeks or more.
Many heroin users who kicked their addiction say that the hardest part of recovery was not the physical withdrawal but the psychological withdrawal. These effects can last much longer. For many months, ex-users may experience major depression, reporting depressive symptoms like constant low mood and anhedonia (the inability to feel pleasure in normally enjoyable activities).
If substance abuse is not always a cause of depression, it can certainly worsen the condition. Many people also resort to drug abuse as a way to manage the pain of their existing depression.
3. Early Childhood Experiences
It’s well known that certain experiences in early childhood are risk factors for depression. This includes traumatic events like the death of a loved one or physical or sexual abuse. Children can also develop the condition if they:
- Experience neglect
- Experience family conflict
- Hear constant criticism
- Grow up with a parent who has depression
Going through a lot of stress in early childhood makes you more vulnerable to stress later in life.
These experiences in early childhood create changes in the brain that are hard to break, but it is possible. One effective treatment is psychodynamic therapy, which focuses on your early life experiences and your family dynamics. Transcranial magnetic stimulation (TMS) can also help ease the symptoms of depression without drugs or any invasive procedures.
4. Major Life Events (Both Immediate and Prolonged)
If you’re someone who is already at risk of depression, then a major life event can be enough to trigger the condition. Immediate major life events could include
- Divorce
- A breakup
- A death in the family
- Job loss
- The failure of a business
- Loss of a home to a natural disaster
- A serious physical injury
- Childbirth (known as postpartum depression)
Experiencing longer periods of stress can also cause symptoms of depression. Prolonged stressful life events could include:
- Unemployment
- Homelessness
- Health issues, like a chronic illness
- Chronic pain
- An abusive or unhealthy relationship
- Job-related stress
If you experience two or more of these problems at the same time, it could increase the chances of triggering depression.
It’s important to be aware of what causes this condition, especially if you feel you’re prone to depression because of genetics, a trauma in your past, or something else.
You can protect your mental health by recognizing and understanding the causes of depression, avoiding them if they can be avoided, or coping with them if they can’t be.
Whatever the cause of depression for you, the important thing to remember is that what you feel is real, and it’s treatable. If you are experiencing major depression and are looking for a treatment alternative to antidepressant medication, we’re here to help. Call Success TMS at 855-943-3232 to learn about TMS therapy for depression and seek treatment.