Age is not a number, it is Undefined
How old are you? Technically, this is one of the most pointless questions you could ask someone because it is most likely that they do not know the real answer.
Although we measure our age according to the number of years we have lived (chronological age), none of us know to what extent our bodies have truly aged biologically. Biological ageing is a complex process that speeds up and slows down depending on several factors. Genetics, epigenetics, environment, metabolic rate and lifestyle all play a role in the deterioration of our bodies over time. Since this is a universal phenomenon, and happens to EVERYONE we have somehow come to be so complacent that we rarely question whether we could change this process.
If I were to ask you what you thought the leading cause of death in the world is you would probably name some disease or the other – cancer, malaria, heart disease and the like. If I then asked who is more likely to die of any one of your chosen diseases: an 86 year old or a 20 year old, the answer seems obvious, the 86 year old, of course. So is it the disease that is the cause of death or the state of being of the individual?
While there are tens of thousands of researchers looking for the cure to cancer, Alzheimer’s, heart disease, Diabetes and Osteoporosis there are far fewer scientists focused on curing ageing. We tend to ignore the fact that the onset of these diseases is most commonly linked to age. Essentially, the irony of our lives is that we are in a race against time to cure diseases caused by time itself!
But the plot thickens! We are trapped in a time/ageing paradox where the fact that ageing research and/or clinical trials takes a lifetime to validate, causes researchers (and investors) to shy away from it. Think of it this way: if someone already has cancer and you give them a drug to cure it, you may see its effectiveness within weeks or months or even years. But if you were to give someone a drug that apparently extends their healthy lifetime (and they were already healthy), you’ll never know if it worked until the end of their life and you’d have to still be alive too!
What makes matters worse is the fact that the causes and effects of ageing have been notoriously elusive. There is debate as to whether biology or molecular physics is the true cause of ageing [Read More]. While a study of the “wellderly” to find the genetic “fountain of youth” also came up short i.e. there is no clear correlation between any particular group of genes and healthy ageing [Read More].
So what do we really know about ageing?
The complexity of ageing is underlined by the fact that we have discovered so many potential contributors to the process of ageing that we are struggling to narrow down on what exactly is the cause of ageing. We may very well have to accept the fact that there are simply multiple contributors to the problem which means (hopefully) that there are multiple solutions to it! Here I have discussed 3 of the major currently standing theories of ageing:
Telomeres and Telomerases: Telomeres are the ends of chromosomes that add on extra genetic material as a buffer for replication and to prevent genes from being shortened during replication. These get shorter with every round of replication and this is considered to be a contributing factor to ageing. The immortality of cells has been linked to the presence of telomerases that are responsible for maintaining telomere length. As telomeres keep shortening over time, and during the course of multiple replications, the cells age
Insulin/nutrient sensing pathways: When the Insulin and insulin-like nutrient sensing pathways are overstimulated, ageing is accelerated. Evidence indicates that the downregulation of these pathways can lead to longer, healthier lifespans in most species. Several chronic disorders of age can be related to this pathway including Type 2 Diabetes and Cardiovascular diseases. Essentially, when this pathway is not functioning efficiently, age related complications are likely to increase.
Oxidative stress: This was the long-standing and possibly the most publicized theory for ageing. The accumulation of reactive free radical species of Oxygen within the cell contribute largely to the deterioration of its integrity and this cell damage leads to ageing. The up-regulation of enzymes that catalyse the efficient capture of these free radicals has shown to be effective in prolonging lifespan.
Overall, in my opinion, ageing boils down to cellular and metabolic efficiency. Every cell has its environmental stresses, as does the organism on the whole. Over-loading the cellular machinery with substances that cause it over-work, reduce the efficiency of break-down and result in symptoms of ageing. Ideally, an efficient handling of nutrients with a balance between inputs and outputs and ability to deal with external stressors allows for maintenance of the cells and organism at optimum conditions (health) for longer – like an engine. So I believe it is time for us to start engineering this efficiency into our systems in order to live longer, healthier, youthful lives!
Note: This is the first of a series of articles that will discuss ageing, its contributors, potential cures and other interesting facts so stay tuned!