Time changes everything except something within us which is always surprised by change (Thomas Hardy.) 
 

Do you ever think about how you are aging? Second by second, hour by hour, day by day, we grow older chronologically. But the signs of biological aging often take us by surprise.? Some aging changes we can recognise.  It gets harder to read  without glasses. Our hair starts to grey. Our joints feel stiff when we first get up. 

But other changes are like the submerged part of an iceberg. Without  specific testing, we don’t know that our immune systems are becoming less efficient, or our kidneys or liver don’t work so well or our bones are getting thinner. 

So is aging inevitable and unchangeable?  The Intrinsic or programmed senescence theories imply that aging is predetermined in our genetic blueprint  like the programming that guides a single cell to grow into a baby. The  extrinsic theories imply that aging results from cumulative damage from environmental exposures to pollutants, toxins  or radiation, that occurs over our lifetime.  

It seems likely that both forces apply. Genes involved in cell maintenance and repair and immune functions are of primary importance in the aging processes and expression of these genes may be sequentially turned on and off by pre-programming. But we also know that oxidative damage to these genes and cells plays an important role in aging and this is something we can possibly control. 

An intriguing question – Do all our body parts and systems age at the same rate? Most people have one or two body systems that plague them more than others. For me it has been my musculo-skeletal system, muscles, bones and joints.   For others it might be brain health or digestive system problems.  Researchers are looking at genes and other biomarkers to differentiate aging of various functions in an individual. For example a person may have the heart function and blood pressure of a young individual, but an aged immune system. 

There are ways in which we can intervene to delay aspects of aging though lifestyle choices. Changes in how and what we eat, our physical activity, even our thoughts can change gene expression. More about that later in the alphabet! 

It certainly seems that is some cases we can turn back time. As for me, I keep wondering when my hair will turn  grey to catch up with my increasing need for stronger reading glasses.  What’s your Achilles’ heel of aging?