What Are the Causes and Symptoms of Depression?

Depression (major depressive disorder) is a common and serious medical illness that negatively affects how you feel, the way you think and how you act. Fortunately, it is also treatable. Depression causes feelings of sadness and/or a loss of interest in activities once enjoyed. It can lead to a variety of emotional and physical problems and can decrease a person’s ability to function at work and at home.

You may be depressed if, for more than two weeks, you've felt sad, down or miserable most of the time, or have lost interest or pleasure in usual activities.It’s important to remember that we all experience some of these symptoms from time to time, and it may not necessarily mean you're depressed. Equally, not everyone who is experiencing depression will have all of these symptoms.

• Behaviour

1. not going out anymore
2. not getting things done at work/school
3. withdrawing from close family and friends
4. relying on alcohol and sedatives
5. not doing usual enjoyable activities
6. unable to concentrate

• Feelings

1. overwhelmed
2. guilty
3. irritable
4. frustrated
5. lacking in confidence
6. unhappy
7. indecisive
8. disappointed
9. miserable
10. sad

• Thoughts

1. 'I’m a failure.'
2. 'It’s my fault.'
3. 'Nothing good ever happens to me.'
4. I’m worthless.
5. 'Life’s not worth living.'
6. 'People would be better off without me.            

• Physical                                                               

1. tired all the time
2. sick and run down
3. headaches and muscle pains
4. churning gut
5. sleep problems
6. loss or change of appetite
7. significant weight loss or gain                                                                                                                                             If you think that you or someone you know may be experiencing depression, completing our checklist is a quick, easy and confidential way to give you more insight. The checklist won't provide a diagnosis – for that you'll need to see a health professional – but it can help to guide you and provide a better understanding of how you're feeling.                                                                                                                                                                      

Causes

Experts believe depression is due to a combination of things:

1. Brain structure; The way certain nerve pathways or circuits in your brain send information may not work properly. Scans show that the parts of your brain involved in mood, thinking, sleep, appetite, and behavior look different when you're depressed, but scientists aren't sure why.    
2. Genes; Scientists are studying certain genes that may make you more likely to get it. But even if you have them, you may not get depressed. And depression can happen in some people even when they don't have that genetic makeup.Depression can run in families, but that doesn't mean you'll develop depression just because someone you're related to has it. And you may have the condition even if no one else in your family has it.
3. Life events; Something disturbing that happens to you may trigger depression. It may be the loss of someone close to you, a difficult relationship, or a stressful situation. Other things, like your finances, where you live, and whether or not you're married may also have an impact. But remember, there doesn't have to be a "reason" for your depression. Sometimes it happens without an obvious cause.
4. Childhood problems; People who have disturbing experiences in childhood are more likely to have depression. It may be from brain changes caused by trauma at a young age.  
5. Other conditions; Drug or alcohol abuse, illness, long-term pain, anxiety, sleep problems, and attention deficit hyperactivity disorder may also be linked to depression.                                                                                                           If you think you're getting depressed, don’t try to tough it out. See your doctor. Lots of treatments can help, including antidepressants and talk therapy. And make sure you get the backing you need from family, friends, and support groups.