Thanks for these articles Lara - useful info yet again

It doesn't surprise me that Serotonin may not be the main indicator of depression. When I was diagnosed with Addison's Disease (adrenal insufficiency) 5+ years ago one of the interesting things I found after starting on replacement dose hydrocortisone (ie: I have to manually replace the cortisol which my body no longer naturally produces) was that too low cortisol levels would produce 'instant' depression. It's noticeable to the point that if you wanted me to be depressed at 9am tomorrow morning just by altering the schedule of the dose I could 'arrange' that. Conversely within 15 mins of taking the dose the depression will be gone. I often wake in the early hours of the morning (ie: low cortisol) in a very maudlin state (I fight the urge to vent here when I'm like that as I know it's temporary).

This may not be the same as the chronic depression that many suffer and I don't mean to make light of the seriousness of any type of depression. I have also experienced the on-going depression that results from frustration with chronic illness, dealing with bureaucracy and inefficient healthcare systems.
IMO 'depression' is such a generalized term, that is too often misused and misunderstood, that it should come with a caveat. More clarity and definition needs to be communicated about depression, by both the medical depression and the media.

I've previously searched for info on a link between cortisol and depression and there is some research out there - sorry I don 't have any references to hand but googling it should turn up something for anyone interested.

There I've had my little rant for the day - thanks for indulging me in reading this - I'd be interested in anyone else thoughts on this.