Hey everyone! Some weeks, the ideas I’m exploring don’t fit neatly beneath a single theme. So here are 3 things I’ve been thinking about lately. I hope they spark your curiosity or offer a fresh idea for supporting your health. Read one or read them all—and reply to let me know your thoughts!

With gratitude,

Dr. Casey

VILPA stands for vigorous intermittent lifestyle physical activity: brief bursts of hard movement embedded in daily life.

I learned about VILPA in my friend Dr. Gabrielle Lyon's book, The Forever Strong PLAYBOOK. It's an awesome concept, especially if you're busy, because it suggests you can get longevity benefits in as little as 4 minutes per day of intense movement associated with everyday activities. I found this to be especially intriguing as a new mama with a full plate!

It’s based on an observational study published in Nature Medicine that followed more than 25,000 non-exercisers in the UK Biobank — average age 62, all reporting no leisure-time exercise and no more than one recreational walk a week — for 6.9 years, tracking movement with wrist-worn accelerometers. Almost all the incidental vigorous activity they picked up came in bouts of a minute or two. The researchers looked at two things separately: how often people had these bursts of activity, and how many total minutes they added up to. Among those who had any VILPA at all, the medians were three bouts and 4.4 total minutes a day.

What counts as VILPA? Think sprinting up stairs, bursts of fast walking while commuting, carrying groceries quickly, walking hard up a hill, or running after your children.

The authors conclude:

The study cannot prove causation, but the associations are dramatic and have a plausible biological basis:

The paper doesn't tell you how to measure VILPA yourself using a wearable, but based on how they describe VILPA activities, these should be quick bursts of daily activity that leave you winded. In my mind, it brings me back to being 21 years old, sprinting through a New York City subway station with 20 pounds of Trader Joe's groceries on each arm, trying to catch my train, and then collapsing into a subway seat. Or, more recently, running through an airport with my baby on my chest, a food bag, a carry-on, and a stroller, trying to make a flight. VILPA! 😆

💡 What to do:

📖 To learn more:

Concrete is the second-most-used material on Earth after water. Humanity uses roughly 30 billion tons each year, which requires an estimated 50 billion metric tons of sand and gravel every year to create. The cement industry accounts for approximately 8% of global carbon dioxide emissions. Between 2011 and 2013, China used more cement than the United States used during the entire twentieth century.

For some reason, I can't stop thinking about this. Earth is a living system that literally breathes — it facilitates the gas exchange that allows us to get oxygen — so what does it mean to seal off so much of its surface? Once the thought popped into my head that paving the Earth is sort of like suffocating a living being, I became more disturbed by concrete and asphalt, and more curious to understand the long-term ramifications of these ubiquitous substances. 

Soil absorbs water, hosts immense biological life, stores carbon, filters water, and helps plants resist drought and disease. Paving it hampers these activities. (Currently, only a small percentage of Earth is paved, but it's rapidly increasing.)

As I was noodling about all this, I heard Counting Crows' cover of "Big Yellow Taxi" and it spoke to all these themes (“They paved paradise, put up a parking lot”), which I took as a "wink from God" to read more about concrete.

So I dug into The World in a Grain: The Story of Sand and How It Transformed Civilization by Vince Beiser. It tells the story of the widespread environmental destruction of the last hundred years related to mass harvesting sand for the concrete and asphalt industries, amongst other industries. The global sand extraction industry has caused bridges to collapse by destabilizing riverbeds, fueled murderous black markets, swallowed coastal farmland, destroyed marine habitats — and, astonishingly, made the type of sand modern civilization depends on increasingly scarce… Usable sand is literally starting to run out (what a metaphor that is... ⏳).

A new generation of building innovators is reimagining the physical world with cool things like self-healing concrete, engineered-timber skyscrapers, and buildings that generate energy, absorb rainfall, and function more like living ecosystems. That feels like progress.

I like to believe some kind of spiritual awakening will get enough of the 8.3 billion people on Earth to care about the web of life that we make vastly different choices than our current extractive culture. But if that doesn’t arrive fast enough, what are the alternatives? Harvesting non-renewable resources from asteroids and doing environmentally damaging manufacturing in space? That’s not science fiction: some of this is already underway. The United States passed a law in 2015 granting companies ownership of resources extracted from asteroids, and several companies are working on industrializing space. The legal scaffolding for moving heavy industry off the planet is already built. We are, it seems, quietly preparing for the possibility that we finish using up the resources on this one. I pray that our sense of stewardship revs up quickly, and this is why I created the Stewards program. 🌍

💡 Does this interest you?

Francis Crick was one of the most important scientists of the 20th century. He co-discovered the double-helix structure of DNA and shared the 1962 Nobel Prize in Physiology or Medicine with James Watson and Maurice Wilkins. One of my favorite books, The Cosmic Serpent: DNA and the Origins of Knowledge by Jeremy Narby, discusses that this scientist actually believed DNA may have arrived on Earth from another civilization. What??! 🤯

It's true: in their 1973 paper on “Directed Panspermia,” Francis Crick and Leslie Orgel proposed that life on Earth may have begun when an earlier advanced alien civilization deliberately sent microorganisms here — "infecting" our planet with life, as they call it. They argued that the universe is old enough for an intelligent species to have arisen before us, and pointed to suggestive clues: molybdenum is relatively scarce on Earth yet essential to important biological reactions, and nearly all terrestrial life uses the same genetic code rather than a diversity of competing codes, as though it descended from a single imported ancestor.

It really is worth reading the original paper — it's only a few pages, and with little scientific jargon, it feels more like a fascinating science fiction read than a wonky paper.

What I love most about Crick's interest in panspermia is that the scientist who helped reveal the structure of DNA was still questioning assumptions and dogma, still spending time critically thinking about what the real truth might be. And throughout his whole life, even after achieving such great success, he was willing to admit how much about life's beginning we still do not understand — at the risk of being humiliated. That is inspiring, and the way I want to live my life. In a world where social media inflames the idea that perceived consensus is reality or certain, it's never been more important for us to each use these beautiful supercomputers sitting in our skulls (🧠) and think critically for ourselves, and explore non-traditional ideas.

💡 Does this interest you?

🗞️ Missed an issue? You can read all past Tuesday newsletters on my website here.