How Not to Age summary

In 2013, the world's leading researchers in the biology of the genetics of aging came together for a workshop in Italy. The goal? To finally answer the question: what is aging?

In the two years of collaboration that followed, these scientists came to a consensus about the essential biological processes that make up the experience of “aging”. Their paper,  “Interventions to Slow Aging in Humans”, identifies eleven essential processes that make up the experience of “aging”. 

Whilst we don’t have time to go into all eleven, let’s look at four of the most important biological phenomena that might help us understand this whole “growing older” thing. They are oxidative stress, autophagy, telomeres, and senescence.

Let’s start with oxidation. If you were to cut open an apple and leave it on your kitchen bench, there’s a good chance it would’ve gone brown when you came back. When the enzymes inside your apple are exposed to air, they react with oxygen to trigger certain chemical compounds to break down. This process is called oxidation, and it happens everywhere in nature – including within your body. 

Oxidative stress is caused by reactive oxygen species, or ROS, which are byproducts of normal cellular metabolism. While ROS are essential for certain cellular functions, excessive ROS can damage DNA, proteins, and lipids. Over time, this damage culminates within the body to cause cellular dysfunction, contributing to aging and various age-related diseases.

Whilst oxidation is making a mess of your body, autophagy is your metabolism’s housekeeping service, cleaning out unwanted or damaged proteins that your body has in storage. Basically, the cells and proteins in our body are constantly being damaged or deteriorating. When we are receiving excess nutrients, the body can build their replacements from fresh ingredients and the old proteins build up. 

But when an enzyme sensor called AMPK alerts your body that it no longer has excess fuel, the cleanup process kicks in. The mechanisms of autophagy begin scrapping the built-up proteins for spare parts. The breakdown products, such as amino acids and fatty acids, are released back into the cell where they can be reused to build new cellular components or used for energy.

Here’s the thing, though – AMPK levels and autophagy both decrease over time, just as the results of oxidative stress start to accumulate. Damaged proteins build up in our body, and we start to see signs of aging. Dysfunctional autophagy has even been linked to various diseases, including cancer, neurodegenerative disorders like Alzheimer's and Parkinson's disease, and infections. 

Later, we’ll look at what we can do to reduce oxidation and boost autophagy, but first, let’s cover two more essential mechanisms in the aging process.