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What is depression?

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What is depression?

Sadness is a normal reaction to life’s disappointments. If the sadness lasts for several weeks, it could be a sign that depression is setting in.

Depression affects mood, cognition, and physical health.  Depression can leave you feeling hopeless, helpless, and chronically overwhelmed. You may have trouble completing everyday tasks. Exhaustion can prevent you from participating in activities that used to be fun. Social and emotional withdrawal from family and friends is common. Irritability is another sign of depression. Depression can also lead to thoughts of death or suicide.

Depression is an illness, just like diabetes or heart disease is an illness. The good news is that depression is highly treatable with talk therapy and medication. And in cases where depression doesn’t lift with drugs and therapy, stronger treatments are available and effective

Symptoms of depression

There are many common signs of depression, but not everyone will experience the same set of symptoms. How long the symptoms last, how serious they are, and how frequently they appear vary from person to person.

According to the National Institute of Mental Health, signs of depression can include:

  • Ongoing feelings of sadness, anxiousness, or emptiness
  • Sense of hopelessness or pessimism
  • Feeling helpless or worthless, or feeling guilty
  • Irritability
  • Restlessness
  • Decreased energy, increased fatigue
  • Decreased interest in formerly pleasurable activities
  • Trouble remembering, concentrating, and making decisions
  • Inability to sleep, or sleeping too much
  • Changes in appetite, either eating too much or too little
  • Suicidal thoughts
  • Ongoing aches and pains, headaches, or digestive troubles that don’t respond to treatment

Keep in mind, depression is a chronic illness. Even after depression is treated, relapses are likely to occur. At least half of the people who suffer from one depressive episode will experience a second with 10 years. Seeking treatment promptly can help minimize depression’s disruptive effects on your life.

What causes depression?

There are no simple answers to this question. Depression arises from many factors. It can develop at any age, even in childhood and during the teen years. Traumatic events, such as the death of a family member or friend, can lead to ongoing depression. Hormonal changes and chronic stress, too, may contribute to depression.

Factors known to influence the development of depression:

  • Stress and psychological factors: Everyone deals with stress differently. What may be unsettling to one person—relationship challenges, moving, graduating from school, or having trouble at work—may be highly stressful to another. It’s not so much that the stress itself causes depression, it’s how a person’s brain chemistry responds to stress.
  • Genetics and family history: A family history of depression points to a greater likelihood of developing depression. But just because there is no family history does not automatically mean you will never experience depression; it can show up in anyone. Likewise, a family history of depression does not automatically mean you will experience bouts of it in your life.
  • Physiological factors: Researchers have found that the hippocampus, a small brain structure that plays a big part in storing memories, is smaller in those who are depressed. At this point, it’s unknown if a small hippocampus contributes to depression or if it is the result of depression.


Neurotransmitters are chemicals that carry signals from one nervous system cell to another. They have a profound effect on how we experience pleasure and mood. Serotonin, norepinephrine, and dopamine are the neurotransmitters most commonly associated with depression. Many depression treatments help balance the level of these neurotransmitters in the brain.

Another brain structure involved in depression is the hypothalamus. It is a small structure at the base of the brain responsible for many bodily functions, such as sleep, appetite, and stress reaction. It’s believed that for neurotransmitters like serotonin, norepinephrine, and dopamine to communicate with the brain, the hypothalamus must be working correctly.

Malfunctioning thyroid gland

Similarly, a malfunctioning thyroid gland can contribute to depression. The thyroid is a small gland at the base of the neck. Among its duties is to produce two hormones that regulate how cells in the body use energy. In some cases, depression results from an underfunctioning thyroid.

Consult a healthcare provider

Because many factors contribute to depression, it is important to consult a healthcare provider, such as your primary care physician, a psychologist, or psychiatrist to help you assess if you’re depressed and to help you find the right treatment.

Common misconceptions

Depression is “all in your head.”
Depression is an illness, just like heart disease is an illness. Symptoms of depression can be both physical and emotional. While researchers continue to look for the precise causes of depression, the medical community does know that both genes, and brain chemistry play a role.

All it takes to get over depression is positive thinking.

Someone who is depressed can’t just snap out of it. Depression arises from a combination of factors, not the least of which is brain chemistry, genes and family history. The good news is that depression is treatable.

Depression happens only because bad things happen in your life.

Everyone experiences ups and downs. But depression is more than feeling sad in response to a loss or disappointment. In fact, depression can develop without any specific negative event. It can come on suddenly, even when everything is going well.

Depression goes away by itself.

Most episodes of depression will eventually go away by themselves. However, depression is a chronic illness, and for most people the depression will come back. Treatment is crucial to shorten the length of time that a person spends depressed, prevent negative consequences while depressed, and delay or prevent relapses.

Antidepressants will lead to personality changes.

Antidepressants work on certain brain chemicals called neurotransmitters. Antidepressants help lift mood by changing the balance of neurotransmitters, but they don’t cause wholesale personality changes.

If you are successful and have all the material comforts in life, you can’t experience depression.

While the stresses of low socioeconomic status can contribute to depression, it is not true that being well-off prevents depression. Depression affects people from every walk of life.

Talking about depression makes it worse.

Keeping depression to yourself can lead to isolation, and isolation makes depression worse. If seeking medical or psychological support feels intimidating at first, find a supportive loved one or friend to talk to. Sharing your feelings is the first step in getting the treatment you need.

Sources: Mental Health America, HealthCentral, World Health Organization

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