Skip to content

The #1 Cause of Depression, According to Science

Everything you need to know about the mood disorder.

According to the Centers for Disease Control and Prevention's 2019 National Health Interview Survey, 4.7 percent of adults over the age of 18 experience regular feelings of depression, with about 1 out of every 6 adults will have depression at some time in their life. While everyone experiences sadness on occasion, how is depression different, who is most likely to get it and what is the number one cause? Read on to learn everything you need to know about depression—and to ensure your health and the health of others, don't miss these Sure Signs You've Already Had COVID.


What Is Depression?

Mature doctor wearing uniform speaking at camera

Mark Pollack, MD, board-certified psychiatrist and chief medical officer for Myriad Mental Health, maker of the GeneSight test explains that depression is a treatable, but serious mental health condition. "It is characterized by feelings of sadness, helplessness, hopelessness, negativity, sleep and appetite disturbances, difficulty concentrating and other symptoms lasting longer than two weeks," he tells Eat This, Not That!

RELATED: Sure Signs You Have "Too Much" Abdominal Fat


What Happens If You Have Depression

Woman crying

Depression impacts everyone differently and can manifest itself in various ways. The CDC offers several symptoms associated with it. 

  • Feeling sad or anxious often or all the time
  • Not wanting to do activities that used to be fun
  • Feeling irritable‚ easily frustrated‚ or restless
  • Having trouble falling asleep or staying asleep
  • Waking up too early or sleeping too much
  • Eating more or less than usual or having no appetite
  • Experiencing aches, pains, headaches, or stomach problems that do not improve with treatment
  • Having trouble concentrating, remembering details, or making decisions
  • Feeling tired‚ even after sleeping well
  • Feeling guilty, worthless, or helpless
  • Thinking about suicide or hurting yourself

RELATED: 7 Signs Someone is Getting Alzheimer's, According to Experts


How Do I Know If I Am Depressed?

depressed woman talking to lady psychologist during session, mental health

Dr. Pollack explains that while there is no blood test for depression, there are screening tools that doctors can use to evaluate whether a person is exhibiting the symptoms of major depressive disorder.

"This screening is important because, while 7 in 10 adults said that they are more conscious about their own or others' mental health challenges than they were before the pandemic began, less than half of adults are very confident they can recognize if a loved one is suffering from depression, according to the GeneSight Mental Health Monitor," he explains. 

RELATED: Virus Experts Warn Don't Go Here Even if It's Open


What Are the Contributing Factors to Depression?

woman stressed at her desk

There are many possible causes of depression. "It is believed that people may be predisposed to depression by a number of factors including changes in brain function, a family history of depression, have suffered stressful life events, adverse social determinants of health like poverty, or have other medical problems," Dr. Pollack states. 

If it's the latter, the CDC reports, for instance, that "evidence shows that mental health disorders—such as depression, anxiety, and PTSD—can develop after cardiac events, including heart failure, stroke, and heart attack." 

RELATED: 7 Ways You're Ruining Your Body After 60, Say Experts


What Is the #1 Cause of Depression

sad senior 70s grandmother look in distance thinking.

Dr. Pollack reveals that scientists have yet to determine a single cause. "It may be caused by a combination of genetic, biological, environmental, and psychological factors," explains the CDC. Although there is so single cause, there are causes that are the #1 most common:

  • Your Age
  • Major Life Events
  • Personal Conflicts
  • Death of Someone Close to You
  • Your Gender—women are twice as likely as men to become depressed
  • Medications or Substance Abuse
  • Serious Illnesses

RELATED: 21 Tips That Improve Your Memory, According to Doctors


Are There Ways You Can Prevent Depression?

Mature fitness woman tie shoelaces on road

Like diabetes and heart disease, depression is a medical disorder and there are ways to help prevent it.  "You may be able to reduce your risk of getting the disorder—like going to therapy with a mental health professional, getting regular exercise, eating a balanced diet, etc. However, just like other disorders, it may not be entirely preventable—due to no fault of the person suffering."

RELATED: 8 Ways You're Ruining Your Body, According to Science


What Should You Do If You Notice Depression Symptoms in Yourself or Others

therapist and patient talking

If you suspect you or a loved one is suffering from depression, you should talk to your doctor as soon as possible, Dr. Pollack encourages. "Depression can and should be treated," he states. They can do a depression screening to assess mental health and discuss treatment options, which can include medication, talk therapy, or other things. 

If using medication as a treatment, he stresses that it's important to know that only about a third of patients achieve remission from their depression with the first medication. "When a medication fails to work for a patient, the clinician may try different medication dosages, change medications or add another medication to what the patient is already taking," he explains.  

Also, it's important that both you and family members/loved one should recognize that depression is not due to a lack of will. "It's an illness like heart disease, diabetes, etc. It is beyond an individual's control, and it will do no good to tell them to 'snap out of it' or 'we all get sad sometimes.' That's akin to telling someone who is suffering a heart attack that you were 'out-of-breath once so you know how it feels.' You should think of your loved one as suffering with a medical condition—and offer the same kindness and support."

He also suggests educating yourself about depression. "The Depression and Bipolar Support Alliance (DBSA) has many resources to help people better support someone with depression. When talking to your loved one, you should be prepared to listen more than talk. You should consider asking your loved one how you can be helpful," he says. 

Finally, he stresses the importance of getting professional help. "It is a critical step in getting well," he says. "Nearly half of those either diagnosed with depression or concerned they may have depression say they would feel ashamed/embarrassed if others found out they were suffering from depression, according to the GeneSight Mental Health Monitor. Yet, you shouldn't let shame or embarrassment prevent your loved ones from getting treatment they need and deserve." And to get through this pandemic at your healthiest, don't miss these 35 Places You're Most Likely to Catch COVID.

Leah Groth
Leah Groth has decades of experience covering all things health, wellness and fitness related. Read more about Leah