This probably doesn't need to be said to anyone who reads Fight Aging! on a regular basis: old people do not die from old age. They die because of specific biological system failures that are caused by a sequence of consequences that can in principle be traced back to an accumulation of cellular and molecular damage, and that damage is a direct byproduct of the normal operation of metabolism. Think of the progression of rust in a complex metal structure as a crude analogy for this situation: simple causes, and a complex progression of structural failure.
Given sufficient time and resources at the time of death it is usually possible to determine with a reasonable degree of accuracy the actual class of system failure responsible. Given a vastly greater knowledge of the exceedingly complex progression of aging in terms of metabolic changes and reactions we could then draw lines of cause and effect all the way back to the fundamental damage. That requires far more effort than the answer is worth, however: the research community will be decades more in making meaningful progress towards that goal, but they will do that work, as the point of science is to gather knowledge. It is fortunate for us that this enormous job can be bypassed on the way to producing treatments for aging; researchers can instead focus on repairing the well-known and well-described fundamental damage resulting from the operation of metabolism. We don't need a full accounting of its progression to effectively treat aging if researchers work on producing ways to periodically repair its causes.
There are other places where people decide that knowledge isn't worth the effort required, and that is in the recording of the cause of death. Statisticians who analyze death records for the old are plagued by the bad habits of pathologists, who in different eras have used various different shorthand notations for "I don't know, I don't have time to find out, this person was old, it happens, moving on now." It used to be the case that "old age" was a fine thing to put on a death certificate, and it still is in many countries, but other more scientific-sounding catch-all categories have come to dominate, giving the appearance of providing information but actually doing nothing of the sort. Some regions are better than others, of course.
Does this matter, really, though? After all, we are interested in repair therapies, which means we are focused on the roots of aging, not its end. Fix the causes and the consequences take care of themselves. Further, the dominant causes of death as a result of the aging process are much more common than the lesser causes, meaning that even with problems in the data is remains fairly clear as to what are the greatest threats to health. Forms of heart disease account for a majority of deaths in the old, for example, and for that collection of age-related diseases you'll find less of the fuzziness in death certificates. Further still, isn't it pedantic and little else to make this distinction between dying from specific things and dying from old age? For regular readers here, maybe. But we still have to convince much of the world, the public at large, that aging is something other than a mysterious process set in stone. I think it makes a difference to talk about dying from specific causes versus "old age." A mystery is something you can't pick apart into jobs to be done and items to be fixed, while a specific cause and mechanism of death invites the question of whether we can do something about it.
The article quoted below is trying, and I think failing, to explain another point of view on why it is that you can't say that people die of old age, via the work of David Gems on aging in model organisms such as nematode worms. If I am following correctly this is the philosophical difference between being killed by accumulating biological damage and its consequences versus being killed by a specific named pathology that could only take hold because you are suffering a high level of damage. To me that's more or less the same thing, damage leading to pathology, but I could envisage situations in which one could frame it the other way. You might look at Gems' recent papers on the evolution of human aging and a definition of longevity enhancing therapies for a better insight into his views.
The answer is no. (Alright, thanks for stopping by!)
Just kidding. But really, people don't die of old age. Though it may seem like a trivial thing to find out, the biology of aging - and the research trailing in its wake - drills down to some pretty profound questions about the nature of existence. But we're getting ahead of ourselves.
"The idea that people die of pure aging, without pathology, is nuts," said Gems, the deputy director of the Institute of Healthy Aging and a professor at the University College London. Here Gems uses "pathology" to refer to something that can kill you - some sort of condition, disease, or ailment - not something so boring and normal as having a lot of birthdays. Something else has to be going on.
"The problem with aging is that it's about the most ghastly and tragic aspect of the human condition. Up until recently, there's been practically nothing one can do about it, so the best thing to do is to lie to oneself about it to make it bearable," said Gems, referring to the relative ease of dying from "old age," rather than crippling pneumonia or the dreaded C-word. "I can't really blame anyone for that, but as a scientist you have to try to understand things as they really are and hope good things come out of that."
If that conclusion feels anticlimactic, or at best grim, you're not alone. Scientists and sci-fi buffs alike haven't been satisfied knowing why we die. The real question, of course, is how we stop dying. If death is just the result of physical breakdown letting in disease, what if the body never breaks down?