Mental Health

What Causes Depression?



Depression is a major health problem. According to the World Health Organization, it is currently the world’s fourth leading disease, and an estimated 121 million people suffer from depression. In Singapore alone, it is reported that 6.3% of Singapore’s adults have experienced depression in their lifetime.

Depression impairs a person’s psychological, social and occupational functioning. Make no mistake, it is a significant health problem, sometimes even leading to health problems or death in serious cases.

Symptoms of Depression

Depressive symptoms include a loss of interest in things that are previously meaningful, and feelings of extreme sadness and low self-worth.

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A Holistic View: The Biopsychosocial Model

The thing is, we can’t just look at health or a disease from one single view. We must include all factors. Health is not just about being free of diseases, it is also about our well-being. To be healthy, we must look at all three domains: our physical health (biology), mental health (psychology), and social health (social). This is the biopsychosocial model.

In depression (as well as all illnesses), all three domains commonly overlap. This is is why treatments that are based on the biopsychosocial model are most successful.

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Let’s have a look at the possible factors, using the biopsychosocial model.

Biological Factors of Depression

Genetics and a person’s biological makeup play a role in their likelihood of having depression. That’s why those who have a family history of depression are also more likely to have it themselves.

One example is this: the serotonin balance in our brains is related to genetics. Serotonin is a neurotransmitter that helps regulate important biological functions, such as sleep, concentration, memory, and appetite. In depression, serotonin levels in our brain becomes imbalanced. As such, our biological functions are affected.

Not only that, depression is also related with a person’s physical health. This can manifest in two ways. One, depression can make a person more vulnerable to having physical illnesses (such as heart diseases). Two, a person who has physical disorders are more likely to develop depression.

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Psychological Factors of Depression

Having too many negative life events, or having too much stress in life, can also lead to higher chances of being depressed. One extremely common cause is working or studying in a stressful environment.

Many people spend a large chunk of time at school or work. Sometimes these environments can be extremely stressful, due to hostile employers or coworkers, heavy workloads, unforgiving customers etc. When stress levels are too high, it can cause people to be unhappy with their jobs. If this goes on for too long, people can become depressed.

Another common cause: past experiences of mental and physical abuse as a child. Victims of childhood abuse (mental and physical) are more likely to becoming depressed, compared to those who have a more happy childhood.

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Social Factors of Depression

People can also become depressed from social factors, such as: experiencing traumatic situations, early separation, lack of social support, or harassment (bullying).

Think of this factor as “the straw that broke the camel’s back”. A major traumatic life event, like losing a loved one, or cyberbullying, or being fired from a job, can make a person depressed.

This seems difficult to understand, but it’s pretty straightforward. All these events have one thing in common: they bring about a mixture of emotions, such as grief, anger, guilt, and anxiety. They all involve the idea of losing something.

And sometimes, people are not equipped to handle these difficult emotions, especially when they are down and under. And that is when people become depressed and sometimes turn to suicidal thoughts.

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The above three factors do and will overlap in most cases. Which leads to my final point. All of us are vulnerable to becoming depressed, some more than others. Here are a few reasons:

(1) Some people are more resilient towards negative events, some less so;
(2) the way we perceive and respond to negative events; and
(3) our ability to cope with negative events.

All these are important, just as all factors are important, when considering something like depression. So widen your view, and your horizons will do so as well.

Read this article to know more about clinical depression.

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