That television advertisement that asks; 'Where does depression hurt?' And the answer, 'Everywhere,' is painfully true, (no pun intended).
But why does depression hurt? After all, it's a mental illness, isn't it? So why do I keep having aches and pains for no apparent reason? Well, yes, it is mental, but it marches in lockstep to your physical make-up. By marching in lockstep, I mean that although depression is partly mental, and this is evidenced by, and in the way that, depressives dream, it has a direct bearing on our physical well-being.
Some years ago, when I suffered major, or clinical, depression, I used to have the most peculiar and vivid dreams. Until I learned more about depression, I had no idea at all that these dreams were actually the cause of my feeling aches and pains all over my body during my waking hours. The point is that people with depression dream three times as much as those who don't suffer from the condition.
The depression-free person dreams about two hours a night, two hours in twenty four, if you like. The depressive, on the other hand. dreams three times that amount. Six hours in twenty four, so he or she spends no less than a quarter of their life dreaming!
The unfortunate part is, though, that while they're dreaming, they're not having the deep, restful sleep that their bodies need to repair themselves. They're in the Rapid Eye Movement, or REM, sleep stage, which is when you dream. To put it very basically, you dream in order that the brain can flush away all the old rubbish that's been built up by your thinking during the previous day. Hardly a medical description, but since the question is; 'Why does depression hurt?' and not the causes of depression, this description will suffice for the moment.
The important point is that the depressive goes through the night in the REM sleep stage for six hours, and a mere two hours in deep sleep. With the non-depressive, this is reversed. Now, because the person with depression is only having two hours, (if they're lucky), of good, deep sleep, their bodies are simply not receiving the rest that they so desperately need. There's nothing restful about the REM sleep stage. It's called Rapid Eye Movement because your eyeballs are constantly moving very quickly from side to side as you dream.
Another problem, and another reason for the aches and pains, is that your serotonin levels drop. Serotonin helps to keep your pain threshold up, so when the levels drop, you become far more susceptible to pain and chronic fatigue.
The big mistake is in thinking that serotonin, or the lack of, is the factor that causes depression. This is totally wrong.
But that's why depression hurts. Too much REM dream sleep and vastly insufficient deep sleep, with a corresponding drop in serotonin levels. Hence, aches and pains.