40. Press Play to Age, Pause to Rewind

Hi friends,

Welcome to the 40th dispatch of How Humans Flourish, a research-informed newsletter on how humans thrive.

This month we’re reading New York Times Bestseller Lifespan: Why We Age—and Why We Don’t Have To by Dr. David Sinclair, world-renowned geneticist and Harvard professor.  

Dr. Sinclair makes a bold claim: Aging is a disease, and like any disease, it’s treatable. At the core of his argument is the “Information Theory of Aging.” To understand how he believes we can slow, or even reverse aging, we first need to look at the origins of life itself.

Dr. Sinclair takes us back 4 billion years, to a time when Earth was a toxic, lifeless planet.  In his words, “organic molecules, having ridden in on the backs of meteorites and comets,” were scattered across volcanic islands. Through a strange alchemy of wetting and drying in primordial pools, these molecules began to form the earliest RNA strands—the predecessors of DNA. Life was about to begin.

These RNA strands were soon encased in fatty acid bubbles, creating primitive cell membranes, which soon frothed as literal scum in these warm primordial pooling lakes. One gene, Magna superstes (Latin for “great survivor”), evolved a key survival mechanism: the ability to repair its DNA. This survival circuit, as Dr. Sinclair explains, is foundational to aging. It’s a system designed to protect us, but over time, it’s also responsible for the breakdown of information in our bodies—a process we now call aging.

This brings us to the epigenome*, which is critical to understanding Sinclair’s theory. While our genome—our complete set of DNA—contains all the instructions to build and maintain our bodies, the epigenome is the “master conductor” that decides which instructions are followed. In simple terms, if the genome is the hardware, the epigenome is the software that determines how the hardware functions.

The epigenome allows genetically identical cells in our bodies to take on specialized roles, like brain, liver, or skin cells. But what makes the epigenome even more fascinating is that it’s adaptable. It responds to environmental factors—what we eat, how much we exercise, the stress we endure. This adaptability is key to our survival, but it also has a downside. Over time, the epigenome can accumulate errors, leading to a breakdown in its ability to regulate gene expression. This deterioration is what drives aging and age-related diseases.

Sinclair argues that aging is essentially a loss of information, particularly in the epigenome. And here’s where his theory becomes revolutionary: if aging is caused by corrupted epigenetic signals, it may be reversible. If we can repair or reset the epigenome, we could potentially restore our cells to a more youthful state.

This idea leads to Sinclair’s concept of longevity genes—genes that help extend both lifespan and healthspan. These genes monitor everything from our diet to our exercise habits, adjusting our bodies to survive the highs and lows of life. He believes now that we understand how these genes work, we have the power to manipulate them through technology, molecules, and even ancient wisdom. The potential to push the boundaries of human longevity is within reach.

Dr. Sinclair marvels, “Given the chaos that exists at the molecular scale, it’s a wonder we survive thirty seconds, let alone make it to our reproductive years, let alone reach 80 more often than not. But we do. Marvelously we do. Miraculously we do. For we are the progeny of a very long lineage of great survivors. Ergo, we are great survivors.” (Sinclair, pg 31 - Kindle)

He continues, “Some of the medical therapies and life-extending technologies discussed in this book are already here. Others are a few years away. And there are more to discuss that are a decade or so down the road..” (Sinclair, pg 121 - Kindle)

What are those therapies and technologies? We’ll explore in the next few weeks.

With gratitude,

*I’m following the groundbreaking work happening in Dr. Rachel Yehuda’s work at Mount Sinai. She’s exploring the concept of intergenerational trauma—how, through our genetic inheritance, we may express epigenetic markers that prepare us for survival in a harsh world. While these markers equip us for toughness, they don’t necessarily open us up to more love, joy, or connection. But here’s the powerful finding: we have the ability to change the expression of these markers… Great survivors we are, indeed.