[Mz]

I cannot answer for Rob, but there can be significant bio-medical factors. I am not really prone to depression. If I am depressed for more than a short period of time, you can bet I am anemic, not sleeping well enough, etc. But I have a serious medical condition and have lived with quite a lot of crazy-making stress over the years. If my brain chemistry is wonky enough, I can be suicidal, in spite of not being the depressive type.

I know a fair amount about such things. I suspect bio-medical/brain chemistry issues are much more common than is generally recognized. I manage a lot of my issues in part with diet. I think a lot more can be done. But I don't know how to get the word out.