What causes depression? Is it something that you’re born with? Is it a chemical imbalance? Is it lifestyle related, or is it your experiences?
Depression and other mood disorders are very complex, and what causes depression is still not entirely understood. It’s become increasingly clear in recent years that the relationship between mind and body is less clear-cut than it was once thought to be, and that there may be a number of different causes of depression: some physiological, some related to experience, and some environmental – or, indeed, a combination of the above.
1. Inflammation of the body
Professor Ed Bulmore of Cambridge University believes that what causes depression is inflammation of the body. He has found that a third of depressed patients (a very significant proportion) show consistently high levels of inflammation.
Just to give you an idea of the difference in levels of inflammation between normal and depressed patients, one depressed patient, interviewed on a BBC World Service broadcast, was found in blood tests to have an inflammation level of 40 where the normal level is just 0.7. In fact, high inflammation levels were such a consistent feature in depressed patients in the research, that it led the professor to conclude that inflammation is not simply a symptom but could actually be what causes depression.
The professor also found that if patients were treated with anti-inflammatory medication, their mood improved rapidly and dramatically “often disproportionately to the amount of inflammation we could actually see”. Researchers at Rice and Ohio State University also came across similar findings that were published in the American Journal of Psychiatry.
2. Intestinal health
Gut health seems to play a major role in what causes depression and this may indeed relate to the previous point regarding inflammation. Inflammation is an immune system response to fight off infection, and gut health has a significant impact on immune system functioning.
Based on evidence from several studies, gut microbiota (that is microorganisms living in the intestines) are strongly linked to several neuropsychiatric disorders, including schizophrenia, anxiety and depression. Gut microorganisms are capable of emitting certain neuroactive substances such as gamma-aminobutyric acid that act on the gut-brain axis. It has also been found in experiments on rodents that pro-biotics have antidepressant and anxiolytic (anxiety relieving) effects.
3. Lack of exercise
When you’re depressed, exercising is just about the last thing you can face doing. It can take all the energy you have just to wash the dishes and get yourself something to eat, never mind going for a run. Also, depression is often accompanied by poor body image, which, rather than being a motivator for getting fit, can actually be a deterrent.
Nevertheless, it has been shown in numerous studies that exercise can considerably improve one’s chances of recovery from depression and help prevent depressive episodes. The thing to do, if you feel depressed, and would like to begin a program of exercise, is to start light and set achievable goals.
Studies on depressed people using an exercise intervention showed that 20-40 minutes of walking, 3 times a week yielded excellent results and that gentle exercise interventions like these were as effective as cognitive therapy in treating depression.
4. Depression contagion
You might be surprised to learn that depression is a contagious illness. A study conducted on college students found that people can ‘catch’ negative thinking habits from a depressed or pessimistic person.
If you’re in a relationship with a depressed person it can be very difficult to avoid getting depressed yourself. Depressed people can’t be talked out of their negative perceptions and are more likely to start influencing your own thinking habits negatively than you are to influence theirs positively.
Psychologists advise being extremely aware in interaction with depressed people and say to make a mental note to silently disagree with what the depressed person is saying. They also advise keeping an eye firmly on your own negative thinking habits and consciously balancing them out with positive or reasonable thoughts.
Finally, they suggest spending time with positive and optimistic people to counter the influence of the negativity coming from your depressed loved one.
Depression can affect anyone: women, men, children, teenagers, and the elderly. In each individual, it can manifest differently. Understanding what causes depression can help us to find appropriate solutions. If you’re depressed, make sure to try simple changes to lifestyle suggested by the above: look for inflammation in the body and try to treat it or prevent it by investigating its causes; start taking a probiotic or eating live yoghurt on a daily basis, especially if you suspect you may have an intestinal disorder; start exercising lightly by incorporating 30 minutes of walking into your daily routine.
Finally, be conscious of how much negativity you’re absorbing from others: instead of allowing it to get you down, suggest some of the solutions mentioned above to your loved one.