Here is a quote from one of the books that I'm reading about longevity. It is from the premise that aging starts at birth (duh!) and that if you can keep your brain young, you can keep your body younger.
"Brain-body medicine has changed the way we think about and ultimately diagnose disease. The irritable bowel syndrome you thought you had can now be traced to an anxiety disorder; the dementia your grandmother suffered from may have been undiagnosed depression; the carbohydrate addiction you once faced turned out to be a dopamine imbalance; or the fibromyalgia your uncle was diagnosed with was a result of a serotonin deficiency. All of these conditions can improve once the source of the problem is recognized."
It is certainly something to think about. I think there might really be something to it. I'm going to keep reading and researching all this and I'll let you know as I find more things.