Is Your City Raising Your Risk of Depression?

Could less air pollution in your town help lower the rates of depression? Maybe, say researchers.

by Lara DeSanto Health Writer

It's not exactly breaking news that pollution can be bad for your physical health, but a new worldwide study adds more evidence to the claim that it can harm your mental health, too.

People with a history of long-term air pollution exposure have increased risk of depression and suicide, according to the systematic review published in Environmental Health Perspectives. So, could decreasing global air pollution stop millions from becoming depressed? It's quite possible, say researchers.

For a person living for at least six months in an area with double the World Health Organization's recommended limit for a type of pollution called fine particle matter (PM2.5) the risk of depression would be increased by about 10% compared with someone living in an area that didn't surpass that limit, per the study. Additionally, short-term exposure—just three days!—to a larger type of pollution (PM10) was associated with a 2% higher risk of suicide.

"We've shown that air pollution could be causing substantial harm to our mental health, making the case for cleaning up the air we breathe even more urgent," said lead study author Isobel Braithwaite of University College London (UCL), in an interview with The Guardian. Her study is the first overview of existing research on air pollution and its link to mental health.

Want to see how your city ranks for air pollution? Check out this handy map from the American Lung Association. No surprise that bigger cities are often the worst culprits (looking at you, Los Angeles).

What Causes Depression?

The cause of depression has long been studied, and experts agree that there are many factors that work together to impact whether someone gets depression. In short, it's complicated. But some possible root causes include differences in your brain chemistry, hormonal imbalance, and more. Known risk factors beyond air pollution include the following, according to the Mayo Clinic:

  • A past personal history of depression or other mental health disorders

  • Abuse of alcohol or drugs

  • Having a serious or chronic illness, like heart disease, chronic pain, or cancer

  • Having experienced traumatic or stressful events, like the loss of a loved one or physical or sexual abuse

  • Taking certain medications, such as certain sleeping pills and high blood pressure drugs

  • A history of depression, suicide, bipolar disorder, or alcoholism in your genetic family

  • Being LGBTQ+ in an unsupportive environment

While there's no guaranteed way to prevent depression from occurring in the first place, taking these steps may be helpful, per the Mayo Clinic:

  • Get your stress under control. Learning to manage your stress can help boost your self-esteem and your resilience, which can help protect you from depression.

  • Build a support system. Having family and/or friends you can reach out to when you're feeling low or in a crisis can help you bounce back quickly and get the support you need.

  • Be proactive about the signs. If you're experiencing signs of depression—such as feelings of sadness and hopelessness, loss of interest and pleasure in activities, a noticeable dip in your energy, or thoughts of death—getting help for depression early can help it from getting worse. Don't be afraid to talk to your doctor about your mental health—they can help you with strategies to cope, rule out other issues, and get you the treatment you may need. The sooner you get help, the better.

Lara DeSanto
Meet Our Writer
Lara DeSanto

Lara is a former digital editor for HealthCentral, covering Sexual Health, Digestive Health, Head and Neck Cancer, and Gynecologic Cancers. She continues to contribute to HealthCentral while she works towards her masters in marriage and family therapy and art therapy. In a past life, she worked as the patient education editor at the American College of OB-GYNs and as a news writer/editor at WTOP.com.