Peter Attia

More than any other tactical domain we discuss in this book, exercise has the greatest power to determine how you will live out the rest of your life.

If there is one type of food that I would eliminate from everyone’s diet if I could, it would be fructose-sweetened drinks, including both sodas and fruit juices, which deliver too much fructose, too quickly, to a gut and liver that much prefer to process fructose slowly. Just eat fruit and let nature provide the right amount of fiber and water.

As Centenarian Decathletes, we are no longer training for a specific event, but to become different sort of athlete altogether: an athlete of life.

The fittest people had the lowest mortality rates—by a surprising margin. ... This study found that someone of below-average VO2 max for their age and sex (that is, between the 25th and 50th percentiles) is at double the risk of all-cause mortality compared to someone in the top quartile (75th to 97.6th percentiles). Thus, poor cardiorespiratory fitness carries a greater relative risk of death than smoking.

Longevity may be a game of inches, where relatively small interventions, with cumulative effect, could help us replicate the centenarian’s lifespan and healthspan. Put another way, if we want to outlive our life expectancy and live better longer, we will have to work hard to earn it—through small, incremental changes.

The conundrum we face is that our environment has changed dramatically over the last century or two, in almost every imaginable way—our food supply and eating habits, our activity levels, and the structure of our social networks—while our genes have scarcely changed at all.

Longevity has two components. The first is how long you live, your chronological lifespan, but the second and equally important part is how well you live—the quality of your years. This is called healthspan.

The healthier and more efficient your mitochondria, the greater your ability to utilize fat, which is by far the body’s most efficient and abundant fuel source. This ability to use both fuels, fat and glucose, is called ‘metabolic flexibility.

I am increasingly persuaded that our 24-7 addiction to screens and social media is perhaps our most destructive habit, not only to our ability to sleep but to our mental health in general.

There’s a quote from Paulo Coelho that I think about often: ‘Maybe the journey isn’t so much about becoming anything,’ he writes. ‘Maybe it’s about unbecoming everything that isn’t really you, so you can be who you were meant to be in the first place.’

It turns out that peak aerobic cardiorespiratory fitness, measured in terms of VO2 max, is perhaps the single most powerful marker for longevity.