There is nothing like the warmth of the sun on your face, listening to the wind whisper through the trees, or the gurgle of water. Indeed, you can’t help but feel a bit more relaxed.  Walking barefoot in slightly damp grass and deeply breathing in the fresh air makes you feel in the moment. It also helps you push away the problems of life for a small respite. Many of us have read about the research regarding the benefits of being outdoors in coping with depression, anxiety, bi-polar disorder, and attention deficit disorders.

However, what happens when that outdoor air is in a high pollutant area?  Is it possible that the polluted air may be lending a not so helping hand to your mood and emotional stability?  Scientists explain how air pollution can cause bipolar disorder and depression.

Nature and Coping with Symptoms of Depression and Bi-polar Disorder

While there are a variety of treatments for many of the symptoms of depression and bipolar disorder, they are not a cure-all for the subtle complexity in how these mental illnesses may affect people.

The medical community links depression and bipolar disorder to the following:

  • mood shifts
  • intense sadness
  • lack of motivation
  • fatigue
  • hyperactivity/manic episodes
  • erratic sleep patterns
  • changes in appetite or eating habits
  • decreased cognitive function related to memory, concentration, and focus.

Other subtle symptoms include  the following:

  • effects on self-esteem
  • decreased self-image
  • lack of self-confidence
  • inability to handle stress
  • “foggy brain”
  • inconsistent energy levels

These symptoms require a more personalized approach.  The top suggested method of dealing with these symptoms is therapy with a medical professional.

In addition to therapy, scientists and therapists both agree that exposure to nature has proven to have significant benefits for one’s mental health. It can be as simple as walking through a nearby park, sitting outdoors enjoying the sunlight and fresh breeze, or involving yourself in an outdoor sport, such as basketball, soccer, or swimming.

University Studies on Bi-Polar Disorder and Air Pollution

One such study performed by Stanford scientists was published in Proceedings of the National Academy of Science and demonstrated that a 90-minute walk in an area of greenery reduced the symptoms of rumination and reduced neural activity in an area of the brain, which affects many with mental illness.  Rumination is the act of “negative self-talk,” which many with depression or bipolar disorder tend to do.  Individuals who walked 90 minutes in an urban environment reported no such thought changes nor displayed any changes in the area of their brain most affected by mental illness.

While many studies demonstrate that physical activity outdoors yields the highest results for overall improvement in mental and physical health,  merely looking at a nature image can still have positive effects on your brain and mood.

One such study by scientists from Texas A & M University and the Department of Psychology at the University of Delaware demonstrated this in an article published in Science Direct.  They played a high-stress film for 120 volunteers.  Next, they followed the movie by showing 1 out of 6 different nature or city scenes through a color video with sound.  Afterward, they checked the volunteers for various psychosomatic symptoms that relate to stress. These factors included high blood pressure, increased heart rate, and muscle stiffness.

Nature Therapies

Science proves that the individuals exposed to more scenic, nature images and sounds, recovered from the aforementioned movie faster than those who viewed more urban photos. The study also showed that more of the individuals were more mentally involved in watching nature images than those of the urban views.

There are thousands of studies related to the health benefits of the outdoors.  You might prefer grounding, the Japanese custom of forest bathing, or merely looking outside a window to a beautiful tree. Regardless, nature has positive effects on your physical and mental wellbeing.

It is becoming such a scientifically accepted fact that cities are being reconstructed to allow for more green areas, walking nature paths and sources of flowing water.  Continued studies are being done to determine which specific trees, types of water sources, plants, flowers, etc. elicit the most positive response.

Air Pollution and its Effects on Bi-polar Disorder

Recreating urban areas to make room for more trees, parks, and walking areas is a wonderful gift to all its residents for improving their health.  However, scientists have discovered that air pollution could have a negative impact on one’s mental health as well.

We are all aware that air pollution is deadly, but do you know how harmful it is?

According to W.H.O (World Health Organization),  there are:

  • 2 million deaths related to pollution of the outdoor air
  • 8 million deaths caused by indoor cooking on dirty stoves or from the fuels used.
  • 91% of the world has air pollution levels higher than the recommended amount
  • Air pollutions contribute to:
    • 29% of deaths from lung cancer
    • 24% of the deaths from stroke
    • 25% of the deaths from heart disease
    • 43% of the deaths from lung disease

With air pollution being such a deadly contributor to our physical health, it was only a matter of time before science started looking at its effects on our brain, neurological system, and our mental health.

Some Alarming Facts

An article in the American Psychological Association, Smog in our Brains, lays out a few studies, performed by various scientists,  that demonstrate the potentiality of air pollution creating a decline in our cognitive ability and mental health:

1 – The Impact on Females

Women ages 71-80 who were exposed to higher levels of pollution displayed a further reduction in cognitive ability.

2 – The Impact on Males

Men who had been exposed to black carbon, or soot, via driving in continuous traffic, showed a decline in cognitive ability equivalent to aging by two years

3 – The Effect on Children

Youngsters tracked from birth to the age of ten exposed to black carbon, performed worse on memory, verbal and non-verbal IQ tests.

4 – The Consequences to Animals

Researchers studied the brains of dogs raised in Mexico City, a notoriously polluted city, showed inflammation and significant markers of damage to the brain akin to Alzheimer’s disease. The same scientists then examined 55 children raised in Mexico City and compared them to a less polluted city.  They also showed neuroinflammation and damage to the frontal cortex of the brain.  Inflammation in the brain can lead to Alzheimer’s or Parkinson’s disease and other central nervous system disorders. Additionally, these children tested poorly on memory, cognition, and intelligence.

Mice exposed to Beijing levels of pollution over 10 months showed alarming symptoms as well. They took more time to complete a maze and made more mistakes.  Further, they showed depressive symptoms such as not liking to swim as much and not sipping sugar water as often; both things characteristically enjoyed previously.  When placed on antidepressants, their behavior reverted back.

They also examined their brains.  Thus, they discovered there were changes to the nerve cells in the hippocampus and fewer spines on the neurons in the area.  These spines are what create connections to other nerves.  Without that connection, your memory performs poorly.

5 – A General Observation Across the Board

Another study showed that people who lived in high polluted areas tended to experience more depression and anxiety that those in cleaner air.

bi-polar disorder

Final Thoughts on the Connection Between Bi-polar Disorder and Air Pollution

A recent study published in PLOS shows further links between air pollution and psychiatric disorders of a depressive or bipolar type.  This study examined data from 151 million people from the United States and 1.4 million people from Denmark.   Specifically, the United States examined data from insurance claims, as reported from the IBM MarketScan database.  The claims were reportedly for bipolar disorder, major depression, personality disorders, schizophrenia, epilepsy, and Parkinson’s disease.

Denmark used national registers of all those born from 1979-2002 to study bipolar disorder, schizophrenia, personality disorders, and depression.  They calculated the air pollution exposure for the individuals’ first ten years.  In both studies, scientists linked bipolar and major depression in each country.

All of the studies mentioned are preliminary examinations of the potential of air pollution contributing to bipolar disorder and depression.  Still, science must rule out additional external factors that could bias the data.  Researchers will perform further studies in the coming years. Fortunately, the current studies are now gaining the attention of the EPA and W.H.O.

Of course, this doesn’t mean that you should stay indoors if you live in a highly populated and polluted city.  Strolling in a park or sitting under a tree is still better for your mental health than staying inside.  Scientists may explain how air pollution can cause depression or bipolar disorder. But for now, trees and plants remain the best-proven method to help clear air pollution, and now trees may be a helping hand for mental and emotional health too.