An interesting Philosophical quandary in regards to ageing is considering how life tends to evolve to it's conditions.
A fish that's kept in a bowl will never grow to the size of one in a river, lake or sea/ocean. The main reason is because it's environment defines the parameters that it can live within, to grow beyond those limitations would actually put it at risk from it's own success.
The same can be seen in a bacterium added to a sweet solution within a Petri dish. It will grow right up to the boundary of the dish, but then it will have problems sustaining itself with the limited solution. This causes it to die, but when some of it dies it allows the rest of it to repopulate all over again. This creates a fluctuating level of growth and decline that's seen as an equilibrium.
Such observations gave way to
Conway's Game of Life (simulation) (wikipedia.org)
While all this inclines to identify the parameters for over grow in size, it also imparts the limitation of balance for longevity in the sense that anything trapped in such a cyclic system is limited by the size at which that cycle permits. In the case of the bacterium, it will only live as long as it over populates itself.
The same hypothetical rational could actually be applied to humanity on this planet Earth. Currently we are limited to how far we can extend before it becomes unsustainable, however physically limiting ourselves within the confines of those parameters dooms us to being stuck within that cycle. We as the human race need to be able to use our inventive skills to start pushing those boundaries by increasing food yields, increasing it's availability at low cost to the consumer, looking to populate currently unpopulated areas (not just planet bound). In doing so we'll increase the size of our parameters which in turn would allow us to live healthy longer lives.