An essay on the causes of aging and what we might do to prevent them can be found at the SENS Research Foundation outreach blog:
The diseases of old age. Age-related disease. The diseases of aging. We've all heard this language used by medical experts. But what do we mean by them? What is the mysterious connection between aging and the diseases of aging? And how is SENS Research Foundation targeting that connection to keep people healthy and prevent and cure the suffering of old age's diseases and disabilities?
While we sometimes prefer not to think about it, we all know that people lose their health as they age. Angina, Alzheimer's, breast and prostate cancers, chronic kidney disease ... With rare exceptions caused by birth defects, severe congenital mutations, or traumatic injury, these diseases are never present in young adults. Their first subtle hints crop up in the years between our forties and our seventies, accompanied by the weakening of our muscles (even in athletes), loss of cushioning in our joints, failing of the eyesight, and a generalized decay of the body's resilience and health. Over time, the minor aches and vague malaise of middle age devolve more or less rapidly into clinical diagnoses, leaving us with a rising burden of disease, disability, and dependence.
But why does this happen? What is it about these diseases that causes them to slowly creep into our bodies after decades of relatively healthy life, each joining and building on the others, as if they were so many poorly-coordinated orchestra musicians, playing at different speeds, starting at different times, and raising a cacophony that gets louder and louder until it reveals itself as a terrible, secret symphony? And what can the answers to those questions tell us about what to do about them?